JP2021069385A - Magnetic resonance imaging system and bed control method - Google Patents

Abstract

To improve work efficiency of an inspection.SOLUTION: A magnetic resonance imaging system includes a magnetic resonance imaging device equipped with a bed whose height of a top plate on which a subject is placed can be changed, and an optical imaging device. The magnetic resonance imaging device includes a position control unit for controlling the bed so as to displace the position of the top plate to a first height, which is a height for sending the subject to an imaging space, and a second height and a third height different from the first height. The optical imaging device acquires an image including the bed. The position control unit determines to which height of the first height, the second height, and the third height the position of the top plate is to be displaced, by using the image acquired by the optical imaging device and information related to state transition of an inspection.SELECTED DRAWING: Figure 1

Description

Embodiments of the present invention relate to magnetic resonance imaging systems and sleeper control methods.

Conventionally, in an examination using a magnetic resonance imaging (MRI) device, an engineer such as a radiologist advances the examination while moving the top plate of the bed on which the subject is placed in the vertical and horizontal directions. Be done. At that time, the instruction to move the top plate is generally given manually by the technician, which may reduce the work efficiency of the inspection.

Japanese Unexamined Patent Publication No. 2018-183525 Japanese Unexamined Patent Publication No. 2013-075005 JP-A-2009-291281

An object to be solved by the present invention is to improve the work efficiency of inspection.

The MRI system according to the embodiment includes an MRI apparatus provided with a bed on which the height of the top plate on which the subject is placed can be changed, and an optical imaging apparatus. The MRI apparatus positions the top plate at a first height, which is the height at which the subject is sent to the imaging space, and at a second height and a third height, which are different from the first height. A position control unit for controlling the sleeper so as to displace the sleeper is provided. The optical photographing apparatus acquires an image including the sleeper. The position control unit uses the image acquired by the optical photographing apparatus and the information related to the state transition of the inspection to determine the first height, the second height, and the third height. Of these, it is determined to which height the position of the top plate is to be displaced.

FIG. 1 is a diagram showing a configuration example of an MRI system according to an embodiment. FIG. 2 is a diagram showing a flow of sleeper control performed by the position control function according to the first embodiment. FIG. 3 is a diagram showing a flow of sleeper control performed by the position control function according to the second embodiment. FIG. 4 is a diagram showing a flow of sleeper control performed by the position control function according to the third embodiment.

Hereinafter, embodiments of the MRI system and the sleeper control method according to the present application will be described in detail with reference to the drawings.

(Embodiment)
FIG. 1 is a diagram showing a configuration example of an MRI system according to an embodiment.

For example, as shown in FIG. 1, the MRI system 100 includes an MRI apparatus 110.

The MRI apparatus 110 includes a static magnetic field magnet 1, a gradient magnetic field coil 2, a gradient magnetic field power supply 3, a whole-body RF (Radio Frequency) coil 4, a local RF coil 5, a transmission circuit 6, a reception circuit 7, a pedestal 8, a sleeper 9, and so on. It includes an interface 10, a display 11, a storage circuit 12, and processing circuits 13 to 16.

The static magnetic field magnet 1 generates a static magnetic field in the imaging space in which the subject S is arranged. Specifically, the static magnetic field magnet 1 is formed in a hollow substantially cylindrical shape (including a magnet having an elliptical cross section orthogonal to the central axis), and an imaging space formed on the inner peripheral side thereof. Generates a static magnetic field. For example, the static magnetic field magnet 1 is a superconducting magnet, a permanent magnet, or the like. The superconducting magnet referred to here is composed of, for example, a container filled with a coolant such as liquid helium and a superconducting coil immersed in the container.

The gradient magnetic field coil 2 is arranged inside the static magnetic field magnet 1 and generates a gradient magnetic field in the imaging space in which the subject S is arranged. Specifically, the gradient magnetic field coil 2 is formed in a hollow substantially cylindrical shape (including one having an elliptical cross section orthogonal to the central axis), and the X-axis, Y-axis, and Z that are orthogonal to each other. It has an X coil, a Y coil, and a Z coil corresponding to each of the shafts. The X coil, Y coil, and Z coil generate a gradient magnetic field that changes linearly along each axial direction in the imaging space based on the current supplied from the gradient magnetic field power supply 3. Here, the Z axis is set along the magnetic flux of the static magnetic field generated by the static magnetic field magnet 1. Further, the X-axis is set to be along the horizontal direction orthogonal to the Z-axis, and the Y-axis is set to be along the vertical direction orthogonal to the Z-axis. As a result, the X-axis, Y-axis, and Z-axis form a device coordinate system unique to the MRI device 110.

The gradient magnetic field power supply 3 generates a gradient magnetic field in the imaging space by supplying a current to the gradient magnetic field coil 2. Specifically, the gradient magnetic field power supply 3 individually supplies a current to the X coil, the Y coil, and the Z coil of the gradient magnetic field coil 2 so as to be along the lead-out direction, the phase encoding direction, and the slice direction that are orthogonal to each other. A gradient magnetic field that changes linearly is generated in the imaging space. In the following, the gradient magnetic field along the lead-out direction is referred to as a lead-out gradient magnetic field, the gradient magnetic field along the phase-encoded direction is referred to as a phase-encoded gradient magnetic field, and the gradient magnetic field along the slice direction is referred to as a slice gradient magnetic field. ..

Here, the lead-out gradient magnetic field, the phase-encoded gradient magnetic field, and the slice gradient magnetic field are superimposed on the static magnetic field generated by the static magnetic field magnet 1, respectively, so that the magnetic resonance signal generated from the subject S is spatially positioned information. Is given. Specifically, the lead-out gradient magnetic field imparts position information along the lead-out direction to the magnetic resonance signal by changing the frequency of the magnetic resonance signal according to the position in the lead-out direction. Further, the phase-encoded gradient magnetic field imparts position information along the phase-encoded direction to the magnetic resonance signal by changing the phase of the magnetic resonance signal along the phase-encoded direction. Further, the slice gradient magnetic field applies position information along the slice direction to the magnetic resonance signal. For example, the slice gradient magnetic field is used to determine the direction, thickness, and number of slice regions when the imaging region is a slice region (2D imaging), and when the imaging region is a volume region (3D imaging). , Used to change the phase of the magnetic resonance signal depending on the position in the slice direction. As a result, the axis along the lead-out direction, the axis along the phase encoding direction, and the axis along the slice direction form a logical coordinate system for defining the slice region or volume region to be imaged.

The whole-body RF coil 4 is arranged on the inner peripheral side of the gradient magnetic field coil 2, transmits a high-frequency magnetic field to the subject S arranged in the imaging space, and magnetism generated from the subject S due to the influence of the high-frequency magnetic field. Receive a resonance signal. Specifically, the whole-body RF coil 4 is formed in a hollow substantially cylindrical shape (including one having an elliptical cross section orthogonal to the central axis), and is a high-frequency pulse supplied from the transmission circuit 6. Based on the signal, a high-frequency magnetic field is transmitted to the subject S arranged in the imaging space located on the inner peripheral side thereof. Further, the whole body RF coil 4 receives the magnetic resonance signal generated from the subject S due to the influence of the high frequency magnetic field, and outputs the received magnetic resonance signal to the receiving circuit 7.

The local RF coil 5 receives the magnetic resonance signal generated from the subject S. Specifically, a plurality of types of local RF coils 5 are prepared so that they can be applied to each part of the subject S, and are arranged near the surface of the part to be imaged when the subject S is imaged. Will be done. Then, the local RF coil 5 receives the magnetic resonance signal generated from the subject S due to the influence of the high frequency magnetic field transmitted by the whole body RF coil 4, and outputs the received magnetic resonance signal to the receiving circuit 7. The local RF coil 5 may further have a function of transmitting a high frequency magnetic field to the subject S. In that case, the local RF coil 5 is connected to the transmission circuit 6 and transmits a high frequency magnetic field to the subject S based on the high frequency pulse signal supplied from the transmission circuit 6. For example, the local RF coil 5 is a surface coil or a phased array coil configured by combining a plurality of surface coils as coil elements.

The transmission circuit 6 outputs a high-frequency pulse signal corresponding to the Larmor frequency peculiar to the target nucleus placed in the static magnetic field to the whole-body RF coil 4. Specifically, the transmission circuit 6 includes a pulse generator, a high frequency generator, a modulator, and an amplifier. The pulse generator produces a waveform of a high frequency pulse signal. The high frequency generator generates a high frequency signal of Larmor frequency. The modulator generates a high-frequency pulse signal by modulating the amplitude of the high-frequency signal generated by the high-frequency generator with the waveform generated by the pulse generator. The amplifier amplifies the high frequency pulse signal generated by the modulator and outputs it to the whole body RF coil 4.

The receiving circuit 7 generates magnetic resonance data based on the magnetic resonance signal output from the whole body RF coil 4 or the local RF coil 5, and outputs the generated magnetic resonance data to the processing circuit 14. For example, the receiving circuit 7 includes a selector, a pre-stage amplifier, a phase detector, and an A / D (Analog / Digital) converter. The selector selectively inputs the magnetic resonance signal output from the whole body RF coil 4 or the local RF coil 5. The pre-stage amplifier power-amplifies the magnetic resonance signal output from the selector. The phase detector detects the phase of the magnetic resonance signal output from the pre-stage amplifier. The A / D converter generates magnetic resonance data by converting the analog signal output from the phase detector into a digital signal, and outputs the generated magnetic resonance data to the processing circuit 14. It should be noted that, in each of the processes described here as being performed by the receiving circuit 7, not all the processes need to be performed by the receiving circuit 7, and some of the processes by the whole body RF coil 4 and the local RF coil 5 ( For example, processing by an A / D converter, etc.) may be performed.

The gantry 8 has a hollow bore 8a formed in a substantially cylindrical shape (including an elliptical cross section orthogonal to the central axis), and has a static magnetic field magnet 1, a gradient magnetic field coil 2, and a whole body. It houses the RF coil 4. Specifically, the gantry 8 has an RF coil 4 for the whole body arranged on the outer peripheral side of the bore 8a, a gradient magnetic field coil 2 arranged on the outer peripheral side of the RF coil 4 for the whole body, and a static magnetic field coil 2 on the outer peripheral side of the gradient magnetic field coil 2. The magnetic field magnets 1 are housed in the arranged state. Here, the space in the bore 8a of the gantry 8 becomes the imaging space in which the subject S is arranged at the time of imaging.

The sleeper 9 has a top plate 9a on which the subject S is placed, and a moving mechanism for moving the top plate 9a in the vertical direction and the horizontal direction. Here, the vertical direction is the vertical direction, and the horizontal direction is the direction along the central axis of the static magnetic field magnet 1. With such a configuration, the sleeper 9 can change the height of the top plate 9a by moving the top plate 9a in the vertical direction. Further, the sleeper 9 can change the position of the top plate 9a between the space outside the gantry 8 and the imaging space inside the bore 8a inside the gantry 8 by moving the top plate 9a in the horizontal direction. It has become.

Here, an example will be described in which the MRI apparatus 110 has a so-called tunnel-type structure in which the static magnetic field magnet 1, the gradient magnetic field coil 2, and the whole-body RF coil 4 are each formed in a substantially cylindrical shape. The embodiment is not limited to this. For example, the MRI apparatus 110 has a so-called open type structure in which a pair of static magnetic field magnets, a pair of gradient magnetic field coils, and a pair of RF coils are arranged so as to face each other across an imaging space in which the subject S is arranged. You may be doing it. In such an open structure, the space sandwiched by the pair of static magnetic field magnets, the pair of gradient magnetic field coils and the pair of RF coils corresponds to the bores in the tunnel type structure.

The interface 10 receives various instructions and various information input operations from the operator. Specifically, the interface 10 is connected to the processing circuit 16, converts an input operation received from the operator into an electric signal, and outputs the input operation to the processing circuit 16. For example, the interface 10 includes a trackball for setting imaging conditions and a region of interest (ROI), a switch button, a mouse, a keyboard, a touch pad for performing input operations by touching an operation surface, and a display screen. It is realized by a touch screen in which a mouse and a touch pad are integrated, a non-contact input circuit using an optical sensor, a voice input circuit, and the like. In the present specification, the interface 10 is not limited to those including physical operating parts such as a mouse and a keyboard. For example, an example of the interface 10 includes an electric signal processing circuit that receives an electric signal corresponding to an input operation from an external input device provided separately from the device and outputs the electric signal to a control circuit.

The display 11 displays various information and various images. Specifically, the display 11 is connected to the processing circuit 16 and converts various information and various image data sent from the processing circuit 16 into electrical signals for display and outputs the data. For example, the display 11 is realized by a liquid crystal monitor, a CRT monitor, a touch panel, or the like.

The storage circuit 12 stores various data. Specifically, the storage circuit 12 stores magnetic resonance data and image data. For example, the storage circuit 12 is realized by a semiconductor memory element such as a RAM (Random Access Memory) or a flash memory, a hard disk, an optical disk, or the like.

The processing circuit 13 has a sleeper control function 13a. The sleeper control function 13a controls the operation of the sleeper 9 by outputting an electric signal for control to the sleeper 9. For example, the sleeper control function 13a receives an instruction from the operator to move the top plate 9a in the vertical direction or the horizontal direction via the interface 10 or the operation panel provided on the gantry 8, and the top plate according to the received instruction. The moving mechanism of the sleeper 9 is operated so as to move the 9a. For example, the sleeper control function 13a moves the top plate 9a on which the subject S is placed to the imaging space inside the bore 8a inside the gantry 8 when the subject S is imaged.

The processing circuit 14 has a data collection function 14a. The data collection function 14a collects the magnetic resonance data of the subject S by executing various pulse sequences. Specifically, the data collection function 14a executes various pulse sequences by driving the gradient magnetic field power supply 3, the transmission circuit 6, and the reception circuit 7 according to the sequence execution data output from the processing circuit 16. Here, the sequence execution data is data representing a pulse sequence, the timing at which the gradient magnetic field power supply 3 supplies a current to the gradient magnetic field coil 2, the strength of the supplied current, and the transmission circuit 6 having a high frequency to the whole body RF coil 4. This is information that defines the timing of supplying the pulse signal, the strength of the high-frequency pulse to be supplied, the timing of sampling the magnetic resonance signal by the receiving circuit 7, and the like. Then, the data collecting function 14a receives the magnetic resonance data output from the receiving circuit 7 as a result of executing the pulse sequence, and stores it in the storage circuit 12. At this time, the magnetic resonance data stored in the storage circuit 12 is the position information along each of the lead-out direction, the phase-out direction, and the slice direction by the above-mentioned lead-out gradient magnetic field, phase-encoded gradient magnetic field, and slice gradient magnetic field. Is added, and the data is stored as data representing a two-dimensional or three-dimensional k space.

The processing circuit 15 has an image generation function 15a. The image generation function 15a generates various images based on the magnetic resonance data collected by the processing circuit 14. Specifically, the image generation function 15a reads the magnetic resonance data collected by the processing circuit 14 from the storage circuit 12, and performs reconstruction processing such as Fourier transform on the read magnetic resonance data in two dimensions or three dimensions. Generate a dimensional image. Then, the image generation function 15a stores the generated image in the storage circuit 12.

The processing circuit 16 has an image pickup control function 16a. The image pickup control function 16a controls the entire MRI apparatus 110 by controlling each component of the MRI apparatus 110. Specifically, the imaging control function 16a displays a GUI (Graphical User Interface) for receiving various instructions and input operations of various information from the operator on the display 11, and the input operation received via the interface 10. Accordingly, each component of the MRI apparatus 110 is controlled. For example, the imaging control function 16a generates sequence execution data based on the imaging conditions input by the operator, and outputs the generated sequence execution data to the processing circuit 14 to collect magnetic resonance data. Further, for example, the image pickup control function 16a controls the processing circuit 15 to generate an image based on the magnetic resonance data collected by the processing circuit 14. Further, for example, the image pickup control function 16a reads out the image stored in the storage circuit 12 and displays the read-out image on the display 11 in response to a request from the operator.

Here, each of the above-mentioned processing circuits is realized by, for example, a processor. In that case, the processing function of each processing circuit is stored in the storage circuit 12 in the form of a program that can be executed by a computer, for example. Then, each processing circuit realizes a processing function corresponding to each program by reading each program from the storage circuit 12 and executing the program. In other words, each processing circuit in the state where each program is read has each function shown in each processing circuit of FIG.

Although each processing circuit has been described here as being realized by a single processor, each processing circuit is configured by combining a plurality of independent processors, and each processing function is executed by each processor executing a program. May be realized. Moreover, the processing function which each processing circuit has may be realized by being appropriately distributed or integrated in a single processing circuit or a plurality of processing circuits. Further, in the example shown in FIG. 1, a single storage circuit 12 has been described as storing a program corresponding to each processing function. However, a plurality of storage circuits are distributed and arranged, and the processing circuits are individually stored. The configuration may be such that the corresponding program is read from the circuit.

Each component of the MRI apparatus 110 described above is divided into a photographing room configured as a shield room that shields the indoor space from electromagnetic waves and an operation room for operating the MRI apparatus 110. For example, the static magnetic field magnet 1, the gradient magnetic field coil 2, the whole body RF coil 4, the local RF coil 5, the receiving circuit 7, the gantry 8, the sleeper 9, and the processing circuit 13 are arranged in the photographing room, and the gradient magnetic field power supply 3 is provided. , Transmission circuit 6, interface 10, display 11, storage circuit 12, and processing circuits 14 to 16 are installed in the operation room. If a machine room is provided in addition to the imaging room and the operation room, a part or all of the gradient magnetic field power supply 3, the transmission circuit 6, the storage circuit 12, and the processing circuits 14 to 16 are in the machine room. It may be installed in.

The overall configuration of the MRI apparatus 110 according to the present embodiment has been described above. Under such a configuration, the MRI apparatus 110 according to the present embodiment collects an image necessary for the examination by imaging the subject S when the examination of the subject S is performed.

Here, in the inspection using the MRI apparatus, the inspection is usually carried out by an engineer such as a radiology department while moving the top plate of the bed on which the subject is placed in the vertical direction and the horizontal direction. At that time, the movement of the top plate is generally performed by the MRI apparatus receiving an instruction from an engineer, which may reduce the work efficiency of the inspection.

For example, the technician lowers the top plate to the minimum height and places the subject on the top plate. In addition, the engineer attaches a local RF coil (hereinafter referred to as a coil) to the subject placed on the top plate, raises the top plate to a height that sends it to the imaging space, and further, a magnetic field in the imaging space. Move the top plate horizontally to the center position.

Such movement of the top plate is generally performed by pressing a button on an operation panel provided on the gantry of the MRI apparatus or the like, but the technician operates the top plate while moving the top plate in the vertical direction or the horizontal direction. You have to hold down the button on the panel. Further, even if the MRI device is configured so that the operation of pressing a button is not required while the top plate is being moved, it is necessary to perform the operation of moving the top plate at least at the joint between work, and the inspection is smooth. It may not be possible to proceed. In addition, when attaching the coil to the subject, the technician often does not adjust the position of the top plate to a height that makes it easy to work according to his height, and it is impossible to bend his waist significantly. As a result of working in a posture, the burden may increase and the work may become inefficient. These are factors that reduce the work efficiency of inspections.

For this reason, the MRI system 100 according to the present embodiment is configured to be able to improve the work efficiency of inspection.

Specifically, the MRI system 100 includes a camera 120 located above the sleeper 9. For example, the camera 120 is mounted on the ceiling of the photographing room. Alternatively, the camera 120 may be attached to the end of the pedestal 8 or the berth 9, or may be attached to the wall around the pedestal 8 or the berth 9. The camera 120 is an example of an optical photographing apparatus.

Further, the processing circuit 16 of the MRI apparatus 110 included in the MRI system 100 has a position control function 16b. Here, the position control function 16b has a top plate at a first height, which is the height at which the subject S is sent to the imaging space, and at a second height and a third height, which are different from the first height. The sleeper 9 is controlled so as to displace the position of 9a. At this time, the position control function 16b appropriately transmits an instruction to the sleeper control function 13a of the processing circuit 13 to bring the top plate 9a to the first height, the second height, and the third height. Move it. The position control function 16b is an example of the position control unit.

Then, in the present embodiment, the camera 120 acquires an image including the sleeper 9, and the position control function 16b uses the image acquired by the camera 120 and the information related to the state transition of the inspection to obtain the first image. It is determined to which of the height, the second height, and the third height the position of the top plate 9b is displaced.

According to such a configuration, the top plate 9a can be automatically moved to a height according to the inspection state based on the image acquired by the camera 120. Thereby, according to the present embodiment, the work efficiency of the inspection can be improved.

Hereinafter, a specific application example of the MRI system 100 according to the present embodiment will be described as an example. In the following examples, an example in which the patient is the subject S will be described. Further, in the following embodiment, the work in which the technician attaches or detaches the coil to the top plate 9a and the patient is referred to as "coil setting".

(First Example)
First, the first embodiment will be described. In the first embodiment, the control of the sleeper 9 will be described when it is assumed that the patient can walk, walks by himself / herself to the imaging room, and lies on the top plate 9a of the sleeper 9.

In this embodiment, the height of the top plate 9a is classified into three modes, "patient replacement mode", "coil setting mode", and "magnetic field center movement mode", as described below. Here, the "patient replacement mode" corresponds to the above-mentioned second height. Further, the "coil setting mode" corresponds to the above-mentioned third height. Further, the "magnetic field center movement mode" corresponds to the above-mentioned first height.

The patient replacement mode is a mode representing the height of the top plate 9a suitable for patient replacement. This height does not have to be uniquely determined by the MRI system 100, for example, patient information obtained from HIS (Hospital Information System) or contacted by a technician immediately before the examination (or). The optimum height is calculated based on the information such as height, gender, nationality, etc. included in the (reserved) information, and is updated to the appropriate height each time the patient is replaced. Alternatively, this height may be fine-tuned to an optimum height immediately before the patient replacement, for example, based on the image of the actual patient acquired by the camera 120. For example, the position control function 16b sets the height of the patient replacement mode based on information about the patient.

The coil setting mode is a mode that represents a height suitable for coil setting by an engineer. This height does not have to be uniquely determined by the system. For example, an appropriate height is registered in advance in a database mounted on the storage circuit 12 for each technician, and the technician to be inspected is set when the imaging conditions are set. By setting, it will be updated to the appropriate height. Alternatively, this height may be finely adjusted to an appropriate height immediately before the coil setting, based on, for example, the information of the technician performing the actual work acquired from the camera 120. For example, the position control function 16b sets the height of the coil setting mode based on the information about the operator who performs the coil setting.

The magnetic field center movement mode is a mode representing the height at which the patient is sent to the magnetic field center. This height is a height peculiar to the MRI system 100, and is set to, for example, the maximum height of the top plate 9a in the sleeper 9.

Here, when the heights of the top plates 9a of each mode are compared, in general, there is a magnitude relationship of patient replacement mode <coil setting mode <magnetic field center movement mode. That is, for example, the height of the patient replacement mode is lower than the height of the magnetic field center movement mode and the height of the coil setting mode. Since the optimum height relationship may change depending on the combination of the patient's height and the technician's height, the height relationship of each mode is not limited to this.

Then, in this embodiment, the position control function 16b controls the sleeper as follows. Each process described below is realized, for example, by the processing circuit 16 reading a predetermined program corresponding to the position control function 16b from the storage circuit 12 and executing the process.

FIG. 2 is a diagram showing a flow of sleeper control executed by the position control function 16b according to the first embodiment.

[Phase-1: Coil setting (preparation)]
For example, as shown in FIG. 2, the position control function 16b first has the top plate 9a located at the height of the coil setting mode, and the lower side of the patient before the patient is placed on the top plate 9a. When it is determined that the coil (first RF coil) arranged in the above is attached to the top plate 9a, the position of the top plate 9a is displaced to the height of the patient replacement mode.

In this Phase-1, the occipital region of the coil (Spine coil (coil for spinal imaging) and Head coil (coil for head imaging)) placed under the patient before the technician welcomes the patient to the imaging room. Minutes (Poster side, etc.) are mounted on the top plate 9a. At this time, the technician also installs mats, sheets, etc. on the top plate 9a in consideration of patient comfort during the examination. When these operations are performed, it is desirable that the height of the top plate 9a is set to a height suitable for the work of the engineer. Therefore, the position control function 16b positions the top plate 9a at the height of the coil setting mode as an initial state before welcoming the patient to the imaging room, for example.

Then, after the coil setting (preparation) work is completed, the technician moves to the entrance of the imaging room or the anterior room to welcome the patient. As a result, the technician will be out of the frame from the imaging range of the camera 120. Therefore, for example, when the technician detects that the frame is out of the imaging range of the camera 120, the position control function 16b determines that the coil is attached to the top plate 9a and sets the position of the top plate 9a in the patient replacement mode. Displace to the height of.

[Phase-2: Patient guidance (patient moves to bed)]
After that, when the position control function 16b determines that the patient is placed on the top plate 9a while the top plate 9a is located at the height of the patient replacement mode, the position control function 16b sets the height of the top plate 9a to the height of the coil setting mode. Displace the position.

In this Phase-2, the height of the top plate 9a is set to the patient replacement mode, and in that state, the patient walks to the sleeper 9. Then, the patient sits on the top plate 9a and lays down on the bed 9 in the position instructed by the technician (head on magnet side: Head First / foot on magnet side: Feet First, supine / prone position, etc.). .. Then, after the patient lays down and stabilizes, the technician prepares the coil to be attached to the patient for coil setting. Therefore, for example, when the following conditions are satisfied, the position control function 16b determines that the patient is placed on the top plate 9a and displaces the position of the top plate 9a to the height of the coil setting mode.

Condition 1) The camera 120 detected that the patient was on the bed 9.

Condition 2) The camera 120 detected that the patient on the bed 9 was stationary.

Condition 3) It was detected that the technician framed out of the imaging range of the camera 120 (because the technician goes to a storage place such as a shelf).

Here, the position control function 16b may displace the position of the top plate 9a when all of the above three conditions are satisfied (AND), or any one or two of the three conditions. When one is established, the position of the top plate 9a may be displaced.

[Phase-3: Coil setting (for upper part of patient)]
After that, the position control function 16b is a coil (second RF coil) arranged on the upper side of the patient placed on the top plate 9a in a state where the top plate 9a is located at the height of the coil setting mode. When it is determined that the top plate 9a is attached, the position of the top plate 9a is displaced to the height of the magnetic field center movement mode.

In this Phase-3, the height of the top plate 9a is set to the coil setting mode, and in that state, the technician attaches and fixes the coil to the patient, and the biological monitor (electrocardiographic synchronization detector, respiratory synchronization). Install the detector, etc.). The patient is then placed in the center of the magnetic field for imaging. Therefore, for example, the position control function 16b determines that the coil is attached to the patient when the following conditions are satisfied, displaces the position of the top plate 9a to the height of the magnetic field center movement mode, and further, the patient. Moves the top plate 9a in the horizontal direction to a position where the top plate 9a is positioned at the center of the magnetic field in the gantry 8.

Condition 1) The camera 120 detected that the coil was arranged on the sleeper 9.

Condition 2) It was detected that the coil cable was connected to the MRI apparatus 110 and was electrically connected.

Condition 3) The camera 120 detected that the coil on the bed 9 and the patient were stationary.

Condition 4) The camera 120 detected that the technician was away from the sleeper 9 (in order for the technician to get a bird's-eye view of the moving patient of the sleeper 9).

Here, the position control function 16b may displace the position of the top plate 9a when all of the above four conditions are satisfied (AND), or any one or two of the three conditions. When one is established, the position of the top plate 9a may be displaced.

[Phase-4: Top plate drawer after imaging]
After that, the position control function 16b sets the position of the top plate 9a to the height of the coil setting mode when it is determined that the imaging of the patient is completed while the top plate 9a is located at the height of the magnetic field center movement mode. Displace.

In this Phase-4, after the imaging is completed, the top plate 9a on which the patient is placed is moved from the center of the magnetic field to the outside of the gantry 8. Therefore, for example, when any one of the following four conditions is satisfied, the position control function 16b determines that the imaging of the patient is completed, and moves the top plate 9a to the outside of the gantry 8 in the horizontal direction. Further, the position of the top plate 9a is displaced to the height of the coil setting mode.

Condition 1) It was detected that all the set imaging conditions were completed by the imaging control function 16a of the processing circuit 16.

Condition 2) It was detected that the technician pressed the button to end the inspection.

Condition 3) The patient pressed the pay shunt call.

Condition 4) The camera 120 detects a violent movement of the patient during imaging (in this case, for example, the imaging control function 16a forcibly terminates imaging).

Here, the position control function 16b is determined to perform the horizontal movement of the top plate 9a to the outside of the gantry 8 and the displacement to the coil setting mode in a series, but the embodiment is not limited to this. For example, the horizontal direction of the top plate 9a to the outside of the gantry 8 is performed by the operation of the operation panel by the operator, and the position control function 16b shifts to the coil setting mode after the top plate 9a is arranged outside the gantry 8. It may be possible to perform only the displacement of.

[Phase-5: Removal of coil]
After that, the position control function 16b is a coil (second RF coil) arranged above the patient from the patient placed on the top plate 9a in a state where the top plate 9a is located at the height of the coil setting mode. When it is determined that the top plate 9a has been removed, the position of the top plate 9a is displaced to the height of the patient replacement mode.

In this Phase-5, the height of the top plate 9a is set to the coil setting mode, and in that state, the technician releases the fixation of the patient and removes the coil and the biological monitor. Therefore, for example, the position control function 16b determines that the coil has been removed from the patient placed on the top plate 9a when the following conditions are satisfied, and positions the top plate 9a at the height of the patient replacement mode. To displace.

Condition 1) It was detected that the coil was out of the imaging range of the camera 120 (because the technician returned the coil to a storage location such as a shelf).

Condition 2) The camera 120 detected that the patient was stationary.

Here, the position control function 16b may displace the position of the top plate 9a when all of the above two conditions are satisfied (AND), or any one of the two conditions is satisfied. In some cases, the position of the top plate 9a may be displaced.

[Phase-6: Patient guidance (patient leaves the imaging room)]
The position control function 16b is the height of the coil setting mode when it is determined that the patient placed on the top plate 9a has left the imaging room while the top plate 9a is located at the height of the patient replacement mode. The position of the top plate 9a is displaced.

In this Phase-6, the height of the top plate 9a is set to the patient replacement mode, and in that state, the patient raises his upper body from the lying state, stands up from the sleeper 9, and exits from the imaging room. To do. Therefore, for example, when the following conditions are satisfied, the position control function 16b determines that the patient has left the imaging room and shifts the position of the top plate 9a to the height of the coil setting mode. As a result, the height of the top plate 9a returns to the state (Phase-1) ready to accept the next patient.

Condition 1) It was detected that the patient was out of the imaging range of the camera 120.

Condition 2) It was detected that the technician framed out of the imaging range of the camera 120.

Here, the position control function 16b may displace the position of the top plate 9a when all of the above two conditions are satisfied (AND), or any one of the two conditions is satisfied. In some cases, the position of the top plate 9a may be displaced.

(Second Example)
Next, a second embodiment will be described. In the second embodiment, the control of the bed 9 will be described when it is assumed that the patient is placed on a moving device such as a wheelchair or a stretcher, moves to the imaging room, and lies on the top plate 9a of the bed 9. ..

In this embodiment, the height of the top plate 9a is set to four types, "first patient replacement mode", "second patient replacement mode", "coil setting mode", and "magnetic field center movement mode", as shown below. It is classified into the modes of. Here, the "second patient replacement mode" corresponds to the above-mentioned second height. Further, the "coil setting mode" corresponds to the above-mentioned third height. Further, the "magnetic field center movement mode" corresponds to the above-mentioned first height. In addition, the "first patient replacement mode" corresponds to the new fourth height.

For example, when a patient is placed on a mobile device and moved to the imaging room, when a procedure for lowering the height of the top plate 9a occurs when the patient is transferred from the mobile device to the sleeper 9, the top plate 9a is moved to the moving device. Alternatively, the patient's arm or leg may be pinched. In order to avoid such a risk, it is desirable that the movement of the top plate 9a when transferring the patient from the mobile device to the sleeper 9 is the movement in the ascending direction. Therefore, in the present embodiment, a mode suitable for transferring the patient from the mobile device to the sleeper 9 is defined as the second patient replacement mode, and the height of the top plate 9a is lowered in advance before the transfer. A first patient replacement mode is defined as a mode intended to be kept.

The first patient replacement mode is a mode in which the top plate 9a is arranged at a position lower than the position where the replacement is performed before the patient is transferred from the mobile device to the bed 9. For example, the first patient replacement mode is set to the minimum height of the top plate 9a that can be moved in the sleeper 9.

The second patient replacement mode is a mode representing the height of the top plate 9a suitable for loading the patient from the mobile device to the sleeper 9. This height does not have to be uniquely determined by the system, for example, the appearance shape of mobile devices (eg, wheelchairs, stretchers, etc.) that may be brought into the imaging room and their height (of the patient's waist). (A place close to the height) is registered in the database mounted on the storage circuit 12 in advance, and the mobile device brought into the photographing room is identified based on the actual image acquired by the camera 120. , It is set by getting the corresponding height from the database. Alternatively, this height may be set by, for example, identifying the waist of the patient based on the actual image acquired by the camera 120 and detecting the height. For example, the position control function 16b sets the height of the second patient replacement mode based on the information about the patient.

The coil setting mode is the same as the coil setting mode described in the first embodiment (when imaging a walking patient).

The magnetic field center movement mode is the same as the magnetic field center movement mode described in the first embodiment (when imaging a walking patient).

Here, when the heights of the top plates 9a of each mode are compared, generally, there is a magnitude relationship of the second patient replacement mode <coil setting mode <magnetic field center movement mode. That is, for example, the height of the second patient replacement mode is lower than the height of the magnetic field center movement mode and the height of the coil setting mode. Since the optimum height relationship may change depending on the combination of the patient's height and the technician's height, the height relationship of each mode is not limited to this. However, for the second patient replacement mode and the first patient replacement mode, it is desirable to satisfy the magnitude relationship of the second patient replacement mode <the first patient replacement mode.

Then, in this embodiment, the position control function 16b controls the sleeper as follows. Each process described below is realized, for example, by the processing circuit 16 reading a predetermined program corresponding to the position control function 16b from the storage circuit 12 and executing the process.

FIG. 3 is a diagram showing a flow of sleeper control executed by the position control function 16b according to the second embodiment.

[Phase-1: Coil setting (preparation)]
For example, as shown in FIG. 2, the position control function 16b first has the top plate 9a located at the height of the coil setting mode, and the lower side of the patient before the patient is placed on the top plate 9a. When it is determined that the coil (first RF coil) arranged in the above is attached to the top plate 9a, the position of the top plate 9a at the height of the first patient replacement mode lower than the height of the second patient replacement mode. To displace.

For example, the position control function 16b determines that the coil is attached to the top plate 9a when the technician detects that the technician has framed out from the imaging range of the camera 120, as in the case-1 of the first embodiment. Then, the position of the top plate 9a is displaced to the height of the first patient replacement mode.

[Phase-2a: Patient guidance (patient moves to bed)]
After that, the position control function 16b determines that the moving device is arranged at the position where the patient is to be replaced on the top plate 9a while the top plate 9a is located at the height of the first patient replacement mode. The position of the top plate 9a is displaced to the height of the patient replacement mode.

In this Phase-2a, the height of the top plate 9a is set to the height of the first patient replacement mode, and in that state, the patient is carried on a moving device such as a wheelchair or a stretcher to the imaging room. Is done. Therefore, the position control function 16b moves to a position where the patient is placed on the top plate 9a when, for example, a moving device such as a wheelchair or a stretcher enters the imaging range of the camera 120 and the moving device is stationary thereafter. It is determined that the instrument has been placed, and the position of the top plate 9a is displaced to the height of the second patient replacement mode.

[Phase-2b: Patient guidance (patient moves to bed)]
After that, the position control function 16b states that the patient is placed on the top plate 9a with the top plate 9a positioned at the height of the second patient replacement mode, as in the case-2 of the first embodiment. When it is determined, the position of the top plate 9a is displaced to the height of the coil setting mode.

[Phase-3: Coil setting (for upper part of patient)]
After that, the position control function 16b is applied to the patient placed on the top plate 9a in a state where the top plate 9a is located at the height of the coil setting mode, as in the case-3 of the first embodiment. When it is determined that the coil (second RF coil) arranged on the upper side is attached, the position of the top plate 9a is displaced to the height of the magnetic field center movement mode.

[Phase-4: Bed drawer after imaging]
After that, the position control function 16b determines that the imaging of the patient is completed with the top plate 9a located at the height of the magnetic field center movement mode, as in the Phase-4 of the first embodiment. The position of the top plate 9a is displaced to the height of the coil setting mode.

[Phase-5: Removal of coil]
After that, the position control function 16b is performed from the patient placed on the top plate 9a in a state where the top plate 9a is located at the height of the coil setting mode, as in the case-5 of the first embodiment, from the patient to the patient. When it is determined that the coil (second RF coil) arranged on the upper side has been removed, the position of the top plate 9a is displaced to the height of the patient replacement mode.

[Phase-6: Patient guidance (patient leaves the imaging room)]
In the position control function 16b, similarly to Phase-6 of the first embodiment, the patient placed on the top plate 9a leaves the imaging room in a state where the top plate 9a is located at the height of the patient replacement mode. If it is determined that this has been done, the position of the top plate 9a is displaced to the height of the coil setting mode.

(Third Example)
Next, a third embodiment will be described. In the third embodiment, the sleeper 9 is a dockable table, and the control of the sleeper 9 is performed on the assumption that the patient is placed on the dockable table, moves to the imaging room, and lies on the top plate 9a of the sleeper 9. explain. The "docable table" referred to here is a movable bed that can be attached to and detached from the gantry 8 of the MRI apparatus 110, and has, for example, a moving means such as wheels, and can move the patient inside and outside the imaging room. It is configured as follows.

In this embodiment, the height of the top plate 9a is classified into three modes, "dockable table attachment / detachment mode", "coil setting mode", and "magnetic field center movement mode", as described below. Here, the "second patient replacement mode" corresponds to the above-mentioned second height. Further, the "coil setting mode" corresponds to the above-mentioned third height. Further, the "magnetic field center movement mode" corresponds to the above-mentioned first height.

The dockable table attachment / detachment mode is a mode set to a height suitable for attaching / detaching the dockable table. For example, information on the height of the top plate 9a when the dockable table is attached is stored in the storage circuit 12, and when the dockable table is removed, the height of the top plate 9a is reset to the stored height. To be done. Alternatively, for example, the information of the technician who moves the dockable table may be managed by the database implemented in the storage circuit 12, and when the dockable table is removed, an appropriate height of the top plate 9a may be set for each technician. .. Alternatively, for example, when the dockable table is attached, the height of the technician carrying the dockable table is detected by the camera 120, and when the dockable table is removed, the height of the top plate 9a is set to an appropriate height according to the technician. The height may be fine-tuned.

The coil setting mode is the same as the coil setting mode described in the first embodiment (when imaging a walking patient).

The magnetic field center movement mode is the same as the magnetic field center movement mode described in the first embodiment (when imaging a walking patient).

Then, in this embodiment, the position control function 16b controls the sleeper as follows. Each process described below is realized, for example, by the processing circuit 16 reading a predetermined program corresponding to the position control function 16b from the storage circuit 12 and executing the process.

FIG. 4 is a diagram showing a flow of sleeper control performed by the position control function 16b according to the third embodiment.

[Phase-1: Coil setting (preparation)]
For example, as shown in FIG. 4, in this embodiment, the operation of Phase-1 does not occur, and when the dockable table is attached to the gantry 8, the transition to the following Phase-2 occurs.

[Phase-2: Patient guidance (patient moves to bed)]
First, the position control function 16b displaces the position of the top plate 9a to the height of the coil setting mode when it is determined that the dockable table is attached to the gantry 8 while the patient is placed on the top plate 9a. ..

In this Phase-2, the height of the top plate 9a is set to the dockable table attachment / detachment mode, and in that state, the patient is placed on the dockable table and carried to the imaging room, and the dockable table is attached to the gantry 8. Therefore, for example, when the same conditions as Phase-2 of the first embodiment are satisfied, the position control function 16b determines that the dockable table is attached to the gantry 8 and sets the height of the coil setting mode. The position of the plate 9a is displaced.

[Phase-3: Coil setting (for upper part of patient)]
After that, the position control function 16b is applied to the patient placed on the top plate 9a in a state where the top plate 9a is located at the height of the coil setting mode, as in the case-3 of the first embodiment. When it is determined that the coil (second RF coil) arranged on the upper side is attached, the position of the top plate 9a is displaced to the height of the magnetic field center movement mode.

[Phase-4: Bed drawer after imaging]
After that, the position control function 16b determines that the imaging of the patient is completed with the top plate 9a located at the height of the magnetic field center movement mode, as in the Phase-4 of the first embodiment. The position of the top plate 9a is displaced to the height of the coil setting mode.

[Phase-5: Removal of coil]
After that, the position control function 16b is performed from the patient placed on the top plate 9a in a state where the top plate 9a is located at the height of the coil setting mode, as in the case-5 of the first embodiment. When it is determined that the coil (second RF coil) arranged on the upper side has been removed, the position of the top plate 9a is displaced to the height of the dockable table attachment / detachment mode.

[Phase-6: Patient guidance (patient leaves the imaging room)]
In this embodiment, the work of Phase-6 does not occur, the dockable table is removed from the gantry 8, the work is completed, and the state of Phase-1 is restored.

In each of the above-described embodiments, the position control function 16b sets the height of the coil setting mode based on the information about the operator who performs the coil setting, but the embodiment is not limited to this.

For example, the position control function 16b may set the height of the coil setting mode by further using the information about the physique of the patient in addition to the information about the coil setting engineer. In this case, for example, the position control function 16b acquires information such as height, weight, gender, and nationality of the patient from HIS or the like, and calculates the vertical thickness of the patient based on the acquired information. Then, the position control function 16b is a top plate 9a that positions the upper surface of the patient at a height at which the technician can easily set the coil when the patient is placed on the top plate 9a based on the calculated thickness. Set the height as the height of the coil setting mode. For example, the thicker the patient, the lower the height of the coil setting mode is set, and the smaller the thickness of the patient, the higher the height of the coil setting mode is set.

The examples of the MRI system 100 according to the present embodiment have been described above. As described in the above-described embodiment, in the present embodiment, the camera 120 acquires an image including the sleeper 9, and the position control function 16b has the image acquired by the camera 120 and information related to the state transition of the inspection. To determine which of the first height, the second height, and the third height the position of the top plate 9b is to be displaced by using and.

According to such a configuration, the top plate 9a can be automatically moved to a height according to the inspection state based on the image acquired by the camera 120. Thereby, according to the present embodiment, the work efficiency of the inspection can be improved.

In addition, since the top plate 9a automatically moves even when the technician is away from the sleeper 9, the technician does not have to take time to move the top plate 9a, which improves work efficiency. Goes up. Further, since the top plate 9a is automatically moved to an appropriate height that is easy to work with, the burden on the technician can be reduced.

In the above-described embodiment, an example in which the position control unit in the present specification is realized by the position control function 16b of the processing circuit 16 has been described, but the embodiment is not limited to this. For example, the position control unit in the present specification realizes the same function by hardware only, software only, or a mixture of hardware and software, in addition to the position control function 16b described in the embodiment. It doesn't matter.

Further, the word "processor" used in the above description means, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an integrated circuit for a specific application (Application Specific Integrated Circuit: ASIC), or a programmable logic device. (For example, it means a circuit such as a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA)). The processor realizes the function by reading and executing the program stored in the storage circuit. Instead of storing the program in the storage circuit, the program may be directly embedded in the circuit of the processor. In this case, the processor realizes the function by reading and executing the program embedded in the circuit. Further, the processor of the present embodiment is not limited to the case where it is configured as a single circuit, and a plurality of independent circuits may be combined to be configured as one processor to realize its function.

Here, the program executed by the processor is provided by being incorporated in a ROM (Read Only Memory), a storage circuit, or the like in advance. This program is a file in a format that can be installed or executed on these devices, such as CD (Compact Disk) -ROM, FD (Flexible Disk), CD-R (Recordable), DVD (Digital Versatile Disk), etc. It may be recorded and provided on a computer-readable storage medium. Further, this program may be provided or distributed by being stored on a computer connected to a network such as the Internet and downloaded via the network. For example, this program is composed of modules including each of the above-mentioned functional parts. As actual hardware, the CPU reads a program from a storage medium such as a ROM and executes it, so that each module is loaded on the main storage device and generated on the main storage device.

According to at least one embodiment described above, the work efficiency of inspection can be improved.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, as well as in the scope of the invention described in the claims and the equivalent scope thereof.

100 MRI system 110 MRI device 9 Sleeper 9a Top plate 16 Processing circuit 16b Position control function 120 Camera

Claims (10)

A magnetic resonance imaging system including a magnetic resonance imaging device provided with a bed on which the height of the top plate on which the subject is placed can be changed, and an optical imaging device.
The magnetic resonance imaging apparatus has the top plate at a first height, which is the height at which the subject is sent to the imaging space, and at a second height and a third height, which are different from the first height. A position control unit that controls the sleeper so as to displace the position of
The optical photographing apparatus acquires an image including the sleeper and obtains an image.
The position control unit uses the image acquired by the optical photographing apparatus and the information related to the state transition of the inspection to determine the first height, the second height, and the third height. Of these, it is determined to which height the position of the top plate is to be displaced.
Magnetic resonance imaging system. The second height is lower than the first height and the third height.
The magnetic resonance imaging system according to claim 1. When the position control unit determines that the subject is placed on the top plate while the top plate is located at the second height, the position control unit raises the top plate to the third height. Displace the position,
The magnetic resonance imaging system according to claim 1 or 2. The position control unit is arranged under the subject before the subject is placed on the top plate in a state where the top plate is located at the third height. When it is determined that the RF coil is attached to the top plate, the position of the top plate is displaced to the second height.
The magnetic resonance imaging system according to any one of claims 1 to 3. The subject is placed on a mobile device and moves,
The position control unit
With the top plate located at the third height, the first RF coil placed under the subject is placed on the top plate before the subject is placed on the top plate. When it is determined that the top plate is attached to the top plate, the position of the top plate is displaced to a fourth height lower than the second height.
When it is determined that the moving device is placed at a position where the subject is to be placed on the top plate while the top plate is located at the fourth height, the top plate is set at the second height. Displace the position of
The magnetic resonance imaging system according to any one of claims 1 to 3. The bed is a mobile bed that can be attached to and detached from the frame of the magnetic resonance imaging device.
The position control unit displaces the position of the top plate to the third height when it is determined that the sleeper is attached to the pedestal while the subject is placed on the top plate. ,
The magnetic resonance imaging system according to claim 1 or 2. In the position control unit, a second RF coil arranged on the upper side of the subject is placed on the subject placed on the top plate in a state where the top plate is located at the third height. When it is determined that the top plate is attached, the position of the top plate is displaced to the first height.
The magnetic resonance imaging system according to any one of claims 1 to 5. The position control unit
When it is determined that the imaging of the subject is completed while the top plate is located at the first height, the position of the top plate is displaced to the third height.
When it is determined that the second RF coil arranged on the upper side of the subject has been removed from the subject placed on the top plate while the top plate is located at the third height. In addition, the position of the top plate is displaced to the second height.
The magnetic resonance imaging system according to any one of claims 1 to 7. The position control unit sets the second height based on the information about the subject.
The magnetic resonance imaging system according to any one of claims 1 to 8. A sleeper in which the height of the top plate on which the subject is placed can be changed, a first height that is the height at which the subject is sent to the imaging space, and a second height that is different from the first height. It is performed in a magnetic resonance imaging system including a magnetic resonance imaging apparatus including a position control unit that controls the bed so as to displace the position of the top plate to a height and a third height, and an optical imaging apparatus. It is a sleeper control method
The optical photographing device acquires an image including the sleeper and obtains an image.
The position control unit uses the image acquired by the optical imaging device and the information related to the state transition when the subject is inspected to perform the first height and the second height. A sleeper control method including determining to which height the top plate is to be displaced among the third heights.

Images