Magnetic resonance imaging apparatus, mounting position output method, and mounting position output program

Abstract

To improve imaging reproducibility.SOLUTION: A magnetic resonance imaging apparatus includes an acquisition unit, a selection unit, and an output control unit. The acquisition unit acquires image-related information on at least one of a subject and an RF (Radio Frequency) coil attached to the subject from an image of the subject taken by an optical imaging device. The selection unit selects statistical information on an attaching position of the RF coil on the basis of the image-related information. The output control unit causes the attaching position of the RF coil corresponding to the statistical information to be output.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The embodiments disclosed in this specification and the drawings relate to a magnetic resonance imaging apparatus, an attachment position output method, and an attachment position output program. [Background technology]

[0002] Conventionally, in an examination using a magnetic resonance imaging (MRI) device, an RF coil that receives a magnetic resonance signal is placed near a subject to perform imaging. For example, an RF coil is attached to a subject placed on a tabletop to perform imaging. In such imaging, the quality of the image obtained by imaging may be affected by the position of the RF coil attached to the subject. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-039519 A [Patent Document 2] JP 2018-183525 A Summary of the Invention [Problem to be solved by the invention]

[0004] One of the problems to be solved by the embodiments disclosed in this specification and the drawings is to improve the reproducibility of imaging. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are not limited to the above problem. Problems corresponding to the effects of each configuration shown in the embodiments described later can also be positioned as other problems. [Means for solving the problem]

[0005] A magnetic resonance imaging apparatus according to an embodiment includes an acquisition unit, a selection unit, and an output control unit. The acquisition unit acquires image-related information related to at least one of a subject and an RF (Radio Frequency) coil attached to the subject from an image of the subject captured by an optical imaging device. The selection unit selects statistical information on the attachment position of the RF coil based on the image-related information. The output control unit outputs the attachment position of the RF coil corresponding to the statistical information. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of an MRI apparatus according to the first embodiment. [Diagram 2] FIG. 2 is a flowchart showing a processing procedure of the MRI apparatus according to the first embodiment. [Diagram 3] FIG. 3 is a diagram showing an example of a camera image according to the first embodiment. [Figure 4] FIG. 4 is a diagram illustrating an example of a statistical information table according to the first embodiment. [Figure 5A] FIG. 5A is a diagram showing a display example by the output control function according to the first embodiment. [Figure 5B] FIG. 5B is a diagram showing a display example by the output control function according to the first embodiment. [Figure 6] FIG. 6 is a flowchart showing a processing procedure of the MRI apparatus according to the second modification of the first embodiment. [Figure 7] FIG. 7 is a diagram showing a display example by the output control function according to the second modification of the first embodiment. [Figure 8] FIG. 8 is a diagram showing a display example by the output control function according to the fifth modification of the first embodiment. [Figure 9] FIG. 9 is a diagram illustrating an example of the configuration of an MRI apparatus according to the second embodiment. [Figure 10] FIG. 10 is a diagram showing a display example by the output control function according to the second embodiment. [Figure 11]FIG. 11 is a diagram showing an example of the configuration of an MRI apparatus according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, a magnetic resonance imaging apparatus, an attachment position output method, and an attachment position output program according to an embodiment will be described with reference to the drawings. Note that the embodiment is not limited to the following embodiment. In addition, the contents described in one embodiment can be applied to other embodiments in the same manner in principle.

[0008] (First embodiment) Fig. 1 is a diagram showing an example of the configuration of an MRI apparatus according to the first embodiment. For example, as shown in Fig. 1, an MRI apparatus 100 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 gantry 8, a bed 9, an interface 10, a display 11, a memory circuit 12, processing circuits 13 to 16, and a camera 17.

[0009] The static magnetic field magnet 1 generates a static magnetic field in an imaging space in which a subject (subject) S is placed. For example, the static magnetic field magnet 1 is formed in a hollow, approximately cylindrical shape (including those in which the cross section perpendicular to the central axis has an elliptical shape), and generates a static magnetic field in an imaging space formed on its inner periphery. For example, the static magnetic field magnet 1 is a superconducting magnet or a permanent magnet. 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.

[0010] The gradient coil 2 is disposed inside the static magnetic field magnet 1, and generates a gradient magnetic field in an imaging space in which the subject S is disposed. Specifically, the gradient coil 2 is formed in a hollow, substantially cylindrical shape (including a shape in which the cross section perpendicular to the central axis is elliptical), and has an X coil, a Y coil, and a Z coil corresponding to the X axis, the Y axis, and the Z axis, which are perpendicular to each other. The X coil, the Y coil, and the Z coil generate a gradient magnetic field in the imaging space that changes linearly along each axis direction based on a current supplied from the gradient magnetic field power supply 3. Here, the Z axis is set to be along the magnetic flux of the static magnetic field generated by the static magnetic field magnet 1. The X axis is set to be along the horizontal direction perpendicular to the Z axis, and the Y axis is set to be along the vertical direction perpendicular to the Z axis. As a result, the X axis, the Y axis, and the Z axis form an apparatus coordinate system unique to the MRI apparatus 100.

[0011] 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 generates a gradient magnetic field in the imaging space that changes linearly along the mutually orthogonal readout direction, phase encoding direction, and slice direction, respectively, by supplying currents individually to the X coil, Y coil, and Z coil of the gradient magnetic field coil 2. In the following, the gradient magnetic field along the readout direction is called a readout gradient magnetic field, the gradient magnetic field along the phase encoding direction is called a phase encoding gradient magnetic field, and the gradient magnetic field along the slice direction is called a slice gradient magnetic field.

[0012] Here, the readout gradient magnetic field, the phase encoding gradient magnetic field, and the slice gradient magnetic field are superimposed on the static magnetic field generated by the static magnetic field magnet 1, thereby providing spatial position information to the magnetic resonance signal generated from the subject S. Specifically, the readout gradient magnetic field changes the frequency of the magnetic resonance signal according to the position in the readout direction, thereby providing the magnetic resonance signal with position information along the readout direction. The phase encoding gradient magnetic field changes the phase of the magnetic resonance signal along the phase encoding direction, thereby providing the magnetic resonance signal with position information along the phase encoding direction. The slice gradient magnetic field provides the magnetic resonance signal with position information along the slice direction. For example, when the imaging region is a slice region (2D imaging), the slice gradient magnetic field is used to determine the direction, thickness, and number of slice regions, and when the imaging region is a volume region (3D imaging), the slice gradient magnetic field is used to change the phase of the magnetic resonance signal according to the position in the slice direction. As a result, the axis along the readout 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.

[0013] The whole-body RF coil 4 is disposed on the inner periphery side of the gradient magnetic field coil 2, transmits a high-frequency magnetic field to the subject S disposed in the imaging space, and receives a magnetic resonance signal generated from the subject S due to the influence of the high-frequency magnetic field. Specifically, the whole-body RF coil 4 is formed in a hollow, substantially cylindrical shape (including a shape in which the cross section perpendicular to the central axis is elliptical), and transmits a high-frequency magnetic field to the subject S disposed in the imaging space located on the inner periphery side thereof based on a high-frequency pulse signal supplied from the transmission circuit 6. In addition, the whole-body RF coil 4 receives a 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 reception circuit 7.

[0014] The local RF coil 5 receives a magnetic resonance signal generated from the subject S. Specifically, a plurality of types of local RF coils 5 are prepared so as to be applicable to each part of the subject S, and are arranged near the surface of the part to be imaged when imaging the subject S. The local RF coil 5 receives a 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 transmitting circuit 6, and transmits a high-frequency magnetic field to the subject S based on a high-frequency pulse signal supplied from the transmitting 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 elements (coil elements). In other words, the local RF coil 5 is not an element itself, but a coil device in which one or a plurality of elements are stored in a housing. The local RF coil 5 may be simply described as an "RF coil" in some cases.

[0015] The transmission circuit 6 outputs to the whole-body RF coil 4 a radio frequency pulse signal corresponding to a Larmor frequency specific to the target atomic nucleus placed in the static magnetic field. Specifically, the transmission circuit 6 has a pulse generator, a radio frequency generator, a modulator, and an amplifier. The pulse generator generates a waveform of the radio frequency pulse signal. The radio frequency generator generates a radio frequency signal at the Larmor frequency. The modulator generates a radio frequency pulse signal by modulating the amplitude of the radio frequency signal generated by the radio frequency generator with the waveform generated by the pulse generator. The amplifier amplifies the radio frequency pulse signal generated by the modulator and outputs it to the whole-body RF coil 4.

[0016] 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 preamplifier, 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 preamplifier power amplifies the magnetic resonance signal output from the selector. The phase detector detects the phase of the magnetic resonance signal output from the preamplifier. 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. Note that, among the processes described here as being performed by the receiving circuit 7, all of the processes do not necessarily have to be performed by the receiving circuit 7, and some of the processes (e.g., processes by an A / D converter, etc.) may be performed by the whole-body RF coil 4 or the local RF coil 5.

[0017] The gantry 8 has a hollow bore 8a formed in a substantially cylindrical shape (including an elliptical shape in a cross section perpendicular to the central axis), and houses the static magnetic field magnet 1, the gradient magnetic field coil 2, and the whole-body RF coil 4. Specifically, the gantry 8 houses the whole-body RF coil 4 on the outer periphery of the bore 8a, the gradient magnetic field coil 2 on the outer periphery of the whole-body RF coil 4, and the static magnetic field magnet 1 on the outer periphery of the gradient magnetic field coil 2. Here, the space within the bore 8a of the gantry 8 becomes an imaging space in which the subject S is placed during imaging. The gantry 8 also has a gantry monitor 8b. The gantry monitor 8b is an example of a display unit.

[0018] The bed 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 and horizontal directions. 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 this configuration, the bed 9 is capable of changing the height of the top plate 9a by moving the top plate 9a in the vertical direction. In addition, the bed 9 is capable of changing the position of the top plate 9a between the space outside the gantry 8 and the imaging space inside the bore 8a of the gantry 8 by moving the top plate 9a in the horizontal direction.

[0019] Here, an example will be described in which the MRI apparatus 100 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, but the embodiment is not limited to this. For example, the MRI apparatus 100 may have 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 to face each other across an imaging space in which the subject S is placed. In such an open-type structure, the space sandwiched between the pair of static magnetic field magnets, the pair of gradient magnetic field coils, and the pair of RF coils corresponds to a bore in the tunnel-type structure.

[0020] The interface 10 accepts input operations of various instructions and various information from an operator. Specifically, the interface 10 is connected to a processing circuit 16, converts the input operations received from the operator into electrical signals, and outputs the electrical signals to the processing circuit 16. For example, the interface 10 is realized by a trackball for setting imaging conditions and a region of interest (ROI), a switch button, a mouse, a keyboard, a touchpad for performing input operations by touching the operation surface, a touch screen in which a display screen and a touchpad are integrated, a non-contact input circuit using an optical sensor, and a voice input circuit. Note that in this specification, the interface 10 is not limited to only those including physical operation parts such as a mouse and a keyboard. For example, an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the device and outputs the electrical signal to a control circuit is also included as an example of the interface 10.

[0021] The display 11 displays various types of information and images. Specifically, the display 11 is connected to the processing circuit 16, and converts data of various types of information and images sent from the processing circuit 16 into electrical signals for display and outputs the electrical signals. For example, the display 11 is realized by a liquid crystal monitor, a CRT monitor, a touch panel, or the like.

[0022] The memory circuitry 12 stores various data. Specifically, the memory circuitry 12 stores magnetic resonance data and image data. For example, the memory circuitry 12 is realized by a semiconductor memory element such as a random access memory (RAM) or a flash memory, a hard disk, an optical disk, or the like. The memory circuitry 12 is an example of a memory unit.

[0023] The processing circuit 13 has a bed control function 13a. The bed control function 13a controls the operation of the bed 9 by outputting a control electric signal to the bed 9. For example, the bed control function 13a receives an instruction to move the top board 9a vertically or horizontally from the operator via the interface 10 or an operation panel provided on the gantry 8, and operates a moving mechanism of the bed 9 to move the top board 9a according to the received instruction. For example, when imaging the subject S, the bed control function 13a moves the top board 9a on which the subject S is placed to an imaging space within a bore 8a inside the gantry 8.

[0024] The processing circuit 14 has a data collection function 14a. The data collection function 14a executes various pulse sequences to collect magnetic resonance data of the subject S. 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 sequence execution data output from the processing circuit 16. Here, the sequence execution data is data representing a pulse sequence, and is information that specifies the timing at which the gradient magnetic field power supply 3 supplies a current to the gradient magnetic field coil 2 and the strength of the current to be supplied, the timing at which the transmission circuit 6 supplies a high-frequency pulse signal to the whole-body RF coil 4 and the strength of the high-frequency pulse to be supplied, the timing at which the reception circuit 7 samples the magnetic resonance signal, and the like. The data collection function 14a receives the magnetic resonance data output from the reception circuit 7 as a result of executing the pulse sequence, and stores it in the memory circuit 12. At this time, the magnetic resonance data stored in the memory circuit 12 is stored as data representing a two-dimensional or three-dimensional k-space by being provided with positional information along each of the readout direction, phase-out direction and slice direction by the aforementioned readout gradient magnetic field, phase encoding gradient magnetic field and slice gradient magnetic field.

[0025] The processing circuitry 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 circuitry 14. Specifically, the image generation function 15a reads out the magnetic resonance data collected by the processing circuitry 14 from the storage circuitry 12, and performs reconstruction processing such as Fourier transform on the read out magnetic resonance data to generate a two-dimensional or three-dimensional image. Then, the image generation function 15a stores the generated image in the storage circuitry 12.

[0026] The processing circuitry 16 controls each component of the MRI apparatus 100 to perform overall control of the MRI apparatus 100. Specifically, the processing circuitry 16 displays a GUI (Graphical User Interface) for receiving various instructions and various information input operations from an operator on the display 11, and controls each component of the MRI apparatus 100 in response to an input operation received via the interface 10. For example, the processing circuitry 16 generates sequence execution data based on imaging conditions input by the operator, and outputs the generated sequence execution data to the processing circuitry 14 to collect magnetic resonance data. Also, for example, the processing circuitry 16 controls the processing circuitry 15 to generate an image based on the magnetic resonance data collected by the processing circuitry 14. Also, for example, the processing circuitry 16 reads out an image stored in the storage circuitry 12 in response to a request from the operator, and displays the read image on the display 11.

[0027] The processing circuit 16 also has an acquisition function 16a, a selection function 16b, and an output control function 16c. Here, the acquisition function 16a is an example of an acquisition unit. The selection function 16b is an example of a selection unit. The output control function 16c is an example of an output control unit. The processing contents of the acquisition function 16a, the selection function 16b, and the output control function 16c will be described later.

[0028] Here, each of the above-mentioned processing circuits is realized by, for example, a processor. In this case, the processing functions of each processing circuit are stored in the storage circuitry 12 in the form of, for example, a program executable by a computer. Then, each processing circuit realizes the processing function corresponding to each program by reading each program from the storage circuitry 12 and executing it. In other words, each processing circuit in a state where each program has been read has each function shown in each processing circuit in FIG. 1.

[0029] Although each processor has been described as being realized by a single processor, each processing circuit may be configured by combining multiple independent processors, and each processor may execute a program to realize each processing function. The processing functions of each processing circuit may be appropriately distributed or integrated into a single or multiple processing circuits. In the example shown in FIG. 1, a single storage circuit 12 is described as storing a program corresponding to each processing function, but multiple storage circuits may be distributed and arranged, and the processing circuits may read out corresponding programs from individual storage circuits.

[0030] The components of the MRI apparatus 100 are arranged separately in an imaging room configured as a shielded room that shields the space inside from electromagnetic waves, and an operation room where the MRI apparatus 100 is operated. 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 bed 9, and the processing circuit 13 are arranged in the imaging room, and the gradient magnetic field power supply 3, the transmitting circuit 6, the interface 10, the display 11, the memory circuit 12, and the 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, some or all of the gradient magnetic field power supply 3, the transmitting circuit 6, the memory circuit 12, and the processing circuits 14 to 16 may be installed in the machine room.

[0031] The camera 17 is an optical imaging device disposed above the bed 9. For example, the camera 17 is attached to the ceiling of an imaging room and captures an overhead image of the surroundings of the bed 9. The image captured by the camera 17 is recorded in, for example, the memory circuit 12 or an external storage device such as a PACS (Picture Archiving and Communication System). The image captured by the camera 17 will be referred to as a "camera image" or a "captured image".

[0032] The camera 17 does not necessarily have to be attached to the ceiling. For example, the camera 17 may be attached to an end of the gantry 8 or the bed 9, or may be attached to a wall around the gantry 8 or the bed 9. Although the case where one camera 17 is provided is described in Fig. 1, two or more cameras may be provided.

[0033] 1, the case where the camera 17 is included in the configuration of the MRI apparatus 100 will be described, but the camera 17 does not necessarily have to be included in the configuration of the MRI apparatus 100. For example, the camera 17 may not be included when the MRI apparatus 100 is shipped, and the camera 17 may be connected as an external device after the MRI apparatus 100 is installed.

[0034] Incidentally, in an MRI apparatus, the mounting position of the local RF coil affects the reproducibility of imaging. For example, the mounting of the local RF coil is performed intuitively based on the technique and experience of the technician (operator), and therefore the mounting position of the local RF coil may be displaced. Therefore, even when a specific scan site is imaged under the same scan conditions, if the mounting position of the local RF coil is displaced, the quality of the obtained image varies, and the reproducibility of imaging decreases. In addition, even when a specific subject is imaged repeatedly at regular intervals for follow-up observation, if the mounting position of the local RF coil is displaced from the mounting position at the time of the previous image capture, the reproducibility of imaging decreases. If the reproducibility of imaging decreases, it may affect the image diagnosis by a doctor, for example, making it difficult to find minute abnormalities (changes) in the affected area.

[0035] Therefore, the MRI apparatus 100 according to the first embodiment executes the following processing functions in order to improve the reproducibility of imaging.

[0036] That is, in the MRI apparatus 100, the acquisition function 16a acquires image-related information related to at least one of the subject S and the local RF coil 5 attached to the subject S from a camera image of the subject S captured by the camera 17. The selection function 16b selects statistical information on the attachment position of the local RF coil 5 based on the image-related information. The output control function 16c outputs the attachment position of the local RF coil 5 corresponding to the statistical information. This allows, for example, the operator to attach the local RF coil 5 to the subject S while referring to the output attachment position of the local RF coil 5. As a result, the MRI apparatus 100 can improve the reproducibility of imaging.

[0037] In the following embodiment, the task of attaching the local RF coil 5 to the subject S by the technician (operator) is referred to as "coil setting." For example, the operator enters an imaging room together with the subject S, places the subject S on the tabletop 9a, and performs coil setting. After completing the coil setting, the operator inserts the tabletop 9a on which the subject S is placed into the bore 8a, and starts imaging by the MRI device 100.

[0038] In the following embodiments, "imaging" by the MRI device 100 and "photographing" by the camera 17 will be described separately. In other words, "imaging" refers to imaging the state inside the body of the subject S by the MRI device 100, and will also be described as "scanning" or "MRI scanning". In addition, "photographing" refers to optically imaging the state within the field of view by the camera 17.

[0039] Fig. 2 is a flowchart showing a processing procedure of the MRI apparatus 100 according to the first embodiment. The processing procedure shown in Fig. 2 is started, for example, when coil setting is started. For example, imaging is performed continuously by the camera 17, and the processing procedure shown in Fig. 2 is started when a person is captured in the camera image. Note that the processing procedure shown in Fig. 2 may be started in response to an instruction from an operator.

[0040] When coil setting is started, the processing circuitry 16 starts recording the camera image (step S101). For example, the processing circuitry 16 starts recording the camera image when a person is captured in the camera image. The processing circuitry 16 presents the recorded camera image to the operator and records the camera image in the memory circuitry 12 or an external storage device such as a PACS.

[0041] Fig. 3 is a diagram showing an example of a camera image according to the first embodiment. As shown in Fig. 3, for example, the camera 17 captures a camera image I10 from above the bed 9 in real time. Then, the output control function 16c displays the captured real-time camera image I10 on the gantry monitor 8b provided on the gantry 8. An image I11 of the subject S and an image I12 of the local RF coil 5 are depicted in the camera image I10. As a result, the operator can view the real-time state of the subject S around the bed 9 on the camera image I10.

[0042] 3 shows, as an example, a case in which the state after the local RF coil 5 is attached to the subject S placed on the tabletop 9a is depicted in the camera image I10, but the present invention is not limited to this. The camera image I10 can provide a moving image of a real-time state within the imaging field of view, such as a state in which a technician who has entered the imaging room and the subject S approach the bed 9, and a state in which the subject S sits on the tabletop 9a.

[0043] Next, the acquisition function 16a recognizes the technician, the subject S, and the local RF coil 5 from the camera image (step S102). For example, the acquisition function 16a individually recognizes the technician, the subject S, and the local RF coil 5 based on the features of the technician, the subject S, and the local RF coil 5 depicted in the camera image.

[0044] For example, a feature of the system is that the technician operates the operation panel of the gantry 8 to adjust the position of the top board 9a. Therefore, the acquisition function 16a executes image recognition from the camera image when the position of the top board 9a is moved. At this timing, the technician is located near the operation panel, and the subject S is located near the bed 9. Therefore, among the people depicted in the camera image, the acquisition function 16a recognizes a person located near the operation panel as a "technician" and a person located near the bed 9 as a "subject S". Alternatively, the acquisition function 16a may recognize a person other than a technician as a "subject S".

[0045] Also, the local RF coil 5 has a feature that it is attached to the subject S by a technician. Therefore, the acquisition function 16a recognizes the local RF coil 5 by performing image recognition on an object held by the technician.

[0046] The above image recognition process is merely an example, and any known image recognition technology can be appropriately selected and applied. For example, when recognizing a person from a camera image, a skeleton recognition technology can be applied.

[0047] The characteristics of the technician, the subject S, and the local RF coil 5 are not limited to the above examples. For example, the technician may be recognized using characteristics such as the technician's work clothes and the technician's nameplate. The subject S may be recognized using characteristics such as the examination clothes, the subject S being in a wheelchair or a stretcher. The local RF coil 5 may be recognized not only by the characteristics on the image, but also by using information obtained from the connector of the local RF coil 5 inserted into the coil port of the bed 9, or by providing the local RF coil 5 with a wireless tag such as an RFID (radio frequency identifier) ​​tag.

[0048] Then, the subject S is placed on the top board 9a (step S103). For example, the subject S stands on the top board 9a according to the instruction of the technician, and waits in the instructed posture.

[0049] Then, the acquiring function 16a acquires image-related information regarding the subject S and the local RF coil 5 (step S104). For example, the acquiring function 16a acquires information indicating the body type, posture, and position of the subject S as the image-related information regarding the subject S.

[0050] For example, the acquisition function 16a acquires height as information indicating the body type of the subject S. As an example, the acquisition function 16a measures the height of the subject S from a camera image of the subject S lying on the top board 9a. Note that the information indicating the body type of the subject S is not limited to height. The acquisition function 16a can acquire at least one of height, abdominal thickness, abdominal width, and limb length as information indicating the body type of the subject S. The abdominal thickness can be measured from a color image when the subject S is lying sideways with respect to the shooting direction of the camera 17. The abdominal width can be measured from a color image when the subject S is facing forward or backward with respect to the shooting direction of the camera 17.

[0051] Moreover, the acquiring function 16a acquires information indicating whether the subject S is lying on his / her back, on his / her stomach, or on his / her side as information indicating the posture of the subject S. As an example, the acquiring function 16a acquires information indicating the posture of the subject S by image recognition from a camera image before (preferably immediately before) the local RF coil 5 is attached to the subject S. This image recognition may be performed by a template corresponding to the posture, or may be performed by skeletal recognition. Moreover, whether the local RF coil 5 is attached can be determined by the timing when the local RF coil 5 (or the technician) is reflected on the top board 9a or the timing when the connector of the local RF coil 5 is inserted into the coil port of the bed 9.

[0052] The acquiring function 16a also acquires position information (coordinates) of the subject S in the camera image as information indicating the position of the subject S. As an example, the position information in the camera image is indicated by a coordinate system in which the vertical direction in the camera image is the y-axis and the horizontal direction is the x-axis. The acquiring function 16a acquires coordinates indicating the center position (center of gravity position) of the subject S from the camera image in a state in which the subject S is placed on the top board 9a. Note that the information indicating the position of the subject S can be indicated by any coordinate system set, such as a coordinate system in the imaging room or a coordinate system on the top board 9a, instead of the coordinate system in the camera image. Furthermore, the position information of the subject S may be indicated by a plurality of coordinates, such as the head, both shoulders, the tips of both hands, and the tips of both feet, instead of the center position.

[0053] Moreover, the acquiring function 16a acquires, as image-related information related to the local RF coil 5, information indicating the current attachment position where the local RF coil 5 is currently attached and the type of the local RF coil 5.

[0054] For example, the acquiring function 16a acquires position information (coordinates) of the local RF coil 5 in the camera image as information indicating the current attachment position of the local RF coil 5. As an example, the acquiring function 16a acquires coordinates indicating the center position (center of gravity position) of the local RF coil 5 from a camera image in a state in which the local RF coil 5 is attached to the subject S. The center position of the local RF coil 5 can be indicated in an arbitrarily set coordinate system such as a coordinate system in the camera image, a coordinate system in the imaging room, or a coordinate system on the top board 9a. The position information of the local RF coil 5 may be indicated by arbitrarily specified multiple coordinates such as the four corners or characteristic structure of the local RF coil 5 instead of the center position.

[0055] The acquiring function 16a also acquires information such as "abdominal coil" and "leg coil" as information indicating the type of the local RF coil 5. As an example, the acquiring function 16a acquires information indicating the type of the local RF coil 5 from a camera image by image recognition using image features of the local RF coil 5. Note that the information indicating the type of the local RF coil 5 may be acquired not only from image features but also from information obtained from a connector of the local RF coil 5 inserted into a coil port of the bed 9, or may be acquired by providing a wireless tag such as an RFID tag in the local RF coil 5.

[0056] The acquiring function 16a also acquires scan conditions for scanning the subject. For example, the acquiring function 16a acquires information indicating a scan site, a coil type, and coil identification information as the scan conditions. Here, the scan site is information indicating a site of the subject S to be scanned, such as "abdomen" or "leg". The coil type is information indicating a type of local RF coil 5 used for scanning, such as "abdomen coil" or "leg coil". The coil identification information is identification information (number, symbol) assigned to each local RF coil 5 to uniquely identify the local RF coil 5 used for scanning. The scan conditions are stored in an arbitrary storage area in the MRI device 100 in association with a patient ID (Identification) of the subject S (patient) to be scanned, and can be acquired arbitrarily.

[0057] In this manner, the acquiring function 16a acquires image-related information regarding the subject S and the local RF coil 5. The acquiring function 16a does not necessarily have to acquire all of the body type of the subject S, the posture of the subject S, and the position (coordinates) of the subject S. In other words, the acquiring function 16a may acquire information indicating at least one of the body type of the subject S, the posture of the subject S, and the position of the subject S.

[0058] Moreover, the acquiring function 16a does not necessarily acquire all of the current attachment position of the local-use RF coil 5 and the type of the local-use RF coil 5. In other words, the acquiring function 16a may acquire information indicating at least one of the current attachment position of the local-use RF coil 5 and the type of the local-use RF coil 5.

[0059] The acquiring function 16a does not necessarily acquire all of the scan region, the coil type, and the coil identification information, that is, the acquiring function 16a may acquire information indicating at least one of the scan region, the coil type, and the coil identification information.

[0060] The selection function 16b selects statistical information on the attachment position of the local RF coil 5 based on the image-related information (step S105). For example, the selection function 16b selects statistical information corresponding to information indicating at least one of the subject's body type, the subject's posture, the subject's position, the coil attachment position, the coil type, the coil identification information, and the scan site.

[0061] 4 is a diagram showing an example of a statistical information table according to the first embodiment. The statistical information table is stored in, for example, the storage circuitry 12, but is not limited thereto and may be stored in any external storage device that can be referenced by the selection function 16b.

[0062] As shown in FIG. 4, for example, the statistical information table stores information in which "statistical ID," "body type," "posture," "subject position," "scan area," "coil type," and "coil mounting position" are associated with each other.

[0063] The "statistical ID" is identification information for uniquely identifying the statistical information stored in the statistical information table. The statistical information table stores information such as "001", "002", and "003" as the statistical ID. The statistical ID is not limited to a numerical value, and may be information in the form of letters, symbols, or a combination of these.

[0064] "Body type" is information indicating the body type of the subject, for example, height [cm]. The statistical information table stores information such as "150-160", "160-170", etc. as body type (height). Note that body type is not limited to height, and may be information indicating at least one of height, abdominal thickness, abdominal width, and limb length.

[0065] "Posture" is information indicating the posture of the subject. The statistical information table stores information such as "supine", "sideways", and "prone" as the posture. Note that the posture is not limited to these, and information indicating any posture can be set.

[0066] "Subject position" is information indicating the position of the subject, and is, for example, coordinates indicating the center position (center of gravity position) of the subject in the camera image. The statistical information table stores information such as "(X1, Y1)", "(X2, Y2)", and "(X3, Y3)" as the subject position. The coordinates indicating the subject position are the average value of the coordinates indicating the subject position in multiple scans performed in the past. The subject position can be indicated in any coordinate system set, such as the coordinate system in the imaging room or the coordinate system on the tabletop 9a, instead of the coordinate system in the camera image. The subject position may also be indicated by multiple coordinates, such as the head, both shoulders, the tips of both hands, and the tips of both feet, instead of the center position.

[0067] "Scanning part" is information indicating the part of the subject to be scanned. The statistical information table stores information indicating the part, such as "abdomen" or "legs", as the scanning part. Note that the scanning part is not limited to these, and information indicating any posture can be set.

[0068] "Coil type" is information indicating the type of local RF coil. The statistical information table stores information such as "abdominal coil" and "leg coil" as the coil type. Note that the coil type is not limited to these, and information indicating any posture can be set.

[0069] The "coil mounting position" is information indicating the position of the local RF coil attached to the subject in the scan, and is, for example, a coordinate indicating the center position (center of gravity position) of the local RF coil in the camera image. The statistical information table stores information such as "(x1, y1)", "(x2, y2)", and "(x3, y3)" as the coil mounting position. The coordinate indicating the coil mounting position is the average value of the coordinate indicating the coil mounting position in multiple scans performed in the past. The coil mounting position can be indicated by an arbitrarily set coordinate system such as a coordinate system in the imaging room or a coordinate system on the top board 9a, instead of a coordinate system in the camera image. The coil mounting position may also be indicated by multiple arbitrarily specified coordinates such as the four corners or characteristic structure of the local RF coil, instead of the center position.

[0070] For example, the statistical information table stores information in which the statistical ID "001", body type "150-160", posture "supine", subject position "(X1, Y1)", scan area "abdomen", coil type "abdominal coil", and coil attachment position "(x1, y1)" are associated with each other. That is, the statistical information of the statistical ID "001" indicates that the average subject position is "(X1, Y1)" and the average coil attachment position is "(x1, y1)" for multiple scans performed under the conditions corresponding to the body type "150-160", posture "supine", scan area "abdomen", and coil type "abdominal coil". The statistical information table also stores various information for the statistical information of other statistical IDs in the same manner.

[0071] The statistical information table illustrated in FIG. 4 is merely an example, and the information stored in the statistical information table can be set arbitrarily. For example, the statistical information table stores a plurality of pieces of statistical information classified according to at least one of the subject's body type, the subject's posture, the subject's position, the coil attachment position, the coil type, the coil identification information, and the scan site. For example, the statistical information table may store statistical information of other statistical IDs, not limited to the statistical IDs "001", "002", and "003" shown in FIG. 4. The statistical information table may store not only the average coordinates of the coil attachment positions, but also each coordinate before averaging. For example, the statistical information table may store information of "(x4, y4)", "(x5, y5)", and "(x6, y6)" as the coil attachment positions in three scans.

[0072] Then, the selection function 16b refers to the statistical information table and selects, from among the multiple pieces of statistical information stored in the statistical information table, statistical information corresponding to the information acquired by the acquisition function 16a.

[0073] For example, a case will be described in which the acquisition function 16a acquires information indicating the height "156 cm", posture "supine", scan area "abdomen", and coil type "abdominal coil" for subject S, who is the subject of coil setting (i.e., the subject to be scanned). In this case, the selection function 16b refers to the statistical information table in FIG. 4 and searches for statistical information corresponding to the information acquired by the acquisition function 16a. Then, the selection function 16b selects the statistical information with statistical ID "001" from the statistical information table in FIG. 4.

[0074] In this way, the selection function 16b selects statistical information on the attachment position of the local RF coil 5 based on the image-related information. Note that the above content is merely an example, and the embodiment is not limited to this. For example, the selection function 16b may select statistical information corresponding to information indicating at least one of the subject's body type, subject's posture, subject's position, coil attachment position, coil type, scan region, and coil identification information as the statistical information.

[0075] For example, the selection function 16b can select statistical information on the attachment position of the local RF coil 5 based on image-related information on at least one of the image-related information on the subject S and the image-related information on the local RF coil 5. For example, when "body type (height)" is acquired as image-related information on the subject S, the selection function 16b can select statistical information based on "body type (height)". Also, when "coil type" is acquired as image-related information on the local RF coil 5, the selection function 16b can select statistical information based on "coil type".

[0076] Returning to the description of Fig. 2, the output control function 16c displays the attachment position of the local RF coil 5 corresponding to the statistical information on the camera image (step S106). For example, the output control function 16c displays the coil attachment position corresponding to the statistical information selected by the selection function 16b on the gantry monitor 8b.

[0077] 5A and 5B are diagrams showing examples of display by the output control function 16c according to the first embodiment. In Fig. 5A and Fig. 5B, a coil attachment position corresponding to statistical information is superimposed on a camera image I10 displayed on the gantry monitor 8b.

[0078] In the example shown in Fig. 5A, the output control function 16c displays a center position image I20 and a contour position image I21 superimposed on a real-time camera image I10. Here, the center position image I20 is a dot-shaped indicator showing the average coil mounting position, and is displayed, for example, at the coil mounting position "(x1, y1)" corresponding to the statistical information of the statistical ID "001". The contour position image I21 is a frame indicator showing the contour position of the local RF coil 5 arranged at the average coil mounting position, and shows, for example, the contour position when the "abdominal coil" corresponding to the statistical information of the statistical ID "001" is displayed at the coil mounting position "(x1, y1)".

[0079] In the example shown in Fig. 5B, the output control function 16c displays three center position images I22 superimposed on the real-time camera image I10. Here, the three center position images I22 are indicators showing the coil mounting positions in three scans before averaging the coil mounting positions. For example, the three center position images I22 are point-shaped indicators showing the positions (coordinates) of the coil mounting positions "(x4, y4)", "(x5, y5)", and "(x6, y6)" in the three scans, respectively.

[0080] In this way, the output control function 16c displays the mounting position of the local RF coil 5 on the camera image in the display form of Fig. 5A or the display form of Fig. 5B. Note that the display examples shown in Fig. 5A and Fig. 5B are merely examples, and the embodiment is not limited to these. For example, the output control function 16c can display the mounting position of the local RF coil 5 in any display form, not limited to the center position image I20, the contour position image I21, and the three center position images I22.

[0081] 5A and 5B show an example of a case where the information is superimposed on the camera image I10, but the embodiment is not limited thereto. For example, the information may be superimposed on a schematic image of the human body, such as an illustration of the human body or a contour line of the human body. In other words, the output control function 16c may superimpose the attachment position of the coil corresponding to the statistical information on the image of the subject S captured by the camera or the schematic image of the human body.

[0082] Also, the display is not necessarily limited to being superimposed. For example, the output control function 16c may display the mounting position corresponding to the statistical information in parallel with the camera image I10.

[0083] In addition, the display unit (display device) on which the mounting position is displayed is not limited to the gantry monitor 8b. For example, the output control function 16c can display the mounting position on any display unit, such as a monitor, display, or tablet other than the gantry monitor 8b. However, it is preferable that the display unit on which the mounting position is displayed is a device that can be installed in the radiography room or is portable.

[0084] The output form by the output control function 16c is not limited to image display by the display unit, and may be output by sound or projection by a projector (projection mapping), for example. Projection by a projector will be described later.

[0085] Returning to the explanation of Fig. 2, the local RF coil 5 is attached to the subject S (step S107). For example, the technician attaches the local RF coil 5 to the subject S while referring to the attachment position of the local RF coil 5 displayed on the gantry monitor 8b. Then, when the technician determines that the local RF coil 5 has been attached in an appropriate attachment position, he or she inserts the connector of the local RF coil 5 into the coil port of the bed 9, completing the coil setting. When the coil setting is completed, the top board 9a on which the subject S is placed is inserted into the bore 8a, and scanning is started.

[0086] The process of step S107 may be carried out to determine the attachment position of the local RF coil 5. For example, after the process of step S103, the technician may place the local RF coil 5 on or near the body of the subject S, and in the process of step S107, adjust the attachment position of the local RF coil 5 as necessary and determine the attachment position.

[0087] Note that the process procedure described in Fig. 2 is merely an example, and the embodiment is not limited thereto. For example, the process procedure shown in Fig. 2 can be arbitrarily changed within a range that does not contradict the process contents. For example, the process of step S104 and the process of step S105 may be executed before the process of step S103.

[0088] As described above, in the MRI apparatus 100 according to the first embodiment, the acquisition function 16a acquires image-related information relating to at least one of the subject S and the local RF coil 5 attached to the subject S from a camera image of the subject S captured by the camera 17. The selection function 16b selects statistical information on the attachment position of the local RF coil 5 based on the image-related information. The output control function 16c outputs the attachment position of the local RF coil 5 corresponding to the statistical information. This allows the MRI apparatus 100 to improve the reproducibility of imaging.

[0089] For example, the MRI apparatus 100 presents a suitable mounting position of the local RF coil 5 to the technician based on a plurality of pieces of statistical information. Therefore, the technician can mount the local RF coil 5 on the subject S while referring to the suitable mounting position of the local RF coil 5. As a result, the MRI apparatus 100 can improve the reproducibility of imaging without depending on the technician's experience or technique.

[0090] (Modification 1 of the first embodiment) For example, in the above embodiment, the output control function 16c can also notify information indicating that the local RF coil 5 has been attached to the attachment position.

[0091] For example, the output control function 16c judges whether the local RF coil 5 has been attached to the attachment position. The judgment of whether the local RF coil 5 has been attached to the attachment position is automatically performed by image recognition of the camera image I10. For example, the output control function 16c compares the current attachment position of the local RF coil 5 recognized from the camera image I10 with the attachment position corresponding to the statistical information. Then, when the distance between the current attachment position of the local RF coil 5 and the attachment position corresponding to the statistical information is within a predetermined range (within a threshold), the output control function 16c judges that the local RF coil 5 has been attached to the attachment position. Then, when the output control function 16c judges that the local RF coil 5 has been attached to the attachment position, for example, a message saying "RF coil has been attached to a suitable attachment position" is displayed on the gantry monitor 8b.

[0092] The output form of the information indicating that the local RF coil 5 has been attached to the attachment position is not necessarily limited to a message. For example, the output control function 16c may notify the information indicating that the local RF coil 5 has been attached to the attachment position by changing the color of the frame of the camera image I10 or the outline position image I21 or by hiding the center position image I20.

[0093] The output form of the information indicating that the local RF coil 5 has been attached to the attachment position does not necessarily have to be notified by different display modes. For example, the output control function 16c may output a message saying "The RF coil has been attached to the appropriate attachment position" by voice, or may notify by sound effects or vibration.

[0094] (Modification 2 of the first embodiment) In the above embodiment, the case where the attachment position of the local RF coil 5 is output has been described, but the embodiment is not limited to this. For example, the MRI apparatus 100 can also output the placement position where the subject S is placed.

[0095] That is, in the MRI apparatus 100 according to the second modification of the first embodiment, the selection function 16b selects statistical information on the placement position where the subject S is placed, based on the image-related information. The output control function 16c outputs the placement position where the subject S is placed, together with the attachment position of the local RF coil 5.

[0096] Fig. 6 is a flowchart showing a processing procedure of the MRI apparatus 100 according to the modified example 2 of the first embodiment. The processing procedure shown in Fig. 6 is different from the processing procedure shown in Fig. 2 in the processes of steps S203 and S204.

[0097] The process procedure shown in Fig. 6 is started, for example, when coil setting is started. The start conditions of the process procedure shown in Fig. 6 are the same as the start conditions of the process procedure shown in Fig. 2.

[0098] When the coil setting is started, the processing circuit 16 starts recording the camera image (step S201). Note that the process of step S201 is similar to the process of step S101 shown in FIG. 2, and therefore the description thereof will be omitted.

[0099] Next, the acquisition function 16a recognizes the technician, the subject S, and the local RF coil 5 from the camera image (step S202). Note that the process of step S202 is similar to the process of step S102 shown in FIG. 2, and therefore the description thereof will be omitted.

[0100] Then, the acquiring function 16a acquires image-related information regarding the subject S (step S203). For example, the acquiring function 16a acquires information indicating at least one of the subject's body type, the subject's posture, and the subject's position. Note that the process of step S203 is similar to the process of acquiring image-related information regarding the subject S in the process of step S104 shown in FIG. 2, and therefore a description thereof will be omitted. Also, if the local RF coil 5 is depicted in the camera image at this point, the acquiring function 16a can also acquire image-related information regarding the local RF coil 5.

[0101] Then, the selection function 16b selects statistical information on the placement position where the subject S is placed, based on the image-related information (step S204). For example, the selection function 16b selects statistical information corresponding to information indicating at least one of the subject's body type, the subject's posture, and the subject's position.

[0102] Specifically, a case will be described in which information indicating a height of "156 cm" and a posture of "lying on one's back" for subject S, who is the subject of coil setting (i.e., the subject to be scanned), is acquired by the acquisition function 16a. In this case, the selection function 16b refers to the statistical information table in FIG. 4 and searches for statistical information corresponding to the information acquired by the acquisition function 16a. Then, the selection function 16b selects statistical information of statistical ID "001" from the statistical information table in FIG. 4. This statistical information of statistical ID "001" is associated with subject position "(X1, Y1)". The subject position is an example of a placement position.

[0103] In this way, the selection function 16b selects statistical information on the placement position at which the subject S is to be placed, based on the image-related information on the subject S.

[0104] Then, the output control function 16c displays the placement position corresponding to the statistical information on the camera image (step S205). For example, the output control function 16c displays the subject position "(X1, Y1)" corresponding to the statistical information selected by the selection function 16b on the gantry monitor 8b.

[0105] Fig. 7 is a diagram showing a display example by the output control function 16c according to the modified example 2 of the first embodiment. Fig. 7 illustrates a case where a subject position corresponding to statistical information is superimposed on a camera image I10 displayed on the gantry monitor 8b.

[0106] In the example shown in Fig. 7, the output control function 16c displays a contour position image I30 superimposed on a real-time camera image I10. Here, the contour position image I30 is a frame indicator showing the contour position of a person placed at an average subject position. For example, the contour position image I30 shows the contour position of a person with a body type of "150-160" corresponding to the statistical information of the statistical ID "001" when displayed at the subject position "(X1, Y1)".

[0107] 7, the output control function 16c displays a center position image I20 and a contour position image I21 superimposed on a real-time camera image I10. The center position image I20 and the contour position image I21 can be displayed by the same process as that described in FIG. 5A, and therefore the description will be omitted.

[0108] In this way, the output control function 16c displays the placement position of the subject S on the camera image in the display form of Fig. 7. Note that the display example shown in Fig. 7 is merely an example, and the embodiment is not limited to this. For example, the output control function 16c can display the attachment position of the local RF coil 5 in any display form, not limited to the contour position image I30. For example, the contour position image I30 may be depicted as a semi-transparent schematic image of the human body, instead of a dashed contour line.

[0109] 7 shows an example in which the mounting position of the local RF coil 5 is displayed, but the present invention is not limited to this. For example, the output control function 16c may not display the mounting position of the local RF coil 5 until the subject S is placed on the top board 9a. The determination as to whether the subject S is placed on the top board 9a may be performed manually by a technician, or may be automatically performed by image recognition of the camera image I10.

[0110] 7 shows an example of a case where the image is superimposed on the camera image I10, but the embodiment is not limited to this. For example, the image may be superimposed on a schematic image of a human body, such as an illustration of the human body or a contour line of the human body. Also, the image is not necessarily limited to a superimposed display. For example, the output control function 16c may display the placement position of the subject S in parallel with the camera image I10.

[0111] In addition, the display unit (display device) on which the placement position is displayed is not limited to the gantry monitor 8b. For example, the output control function 16c can display the placement position on any display unit, such as a monitor, display, or tablet other than the gantry monitor 8b. However, it is preferable that the display unit on which the placement position is displayed is a device that can be installed in the radiography room or is portable.

[0112] The output form by the output control function 16c is not limited to image display by the display unit, and may be output by sound or projection by a projector (projection mapping), for example. Projection by a projector will be described later.

[0113] Returning to the description of Fig. 6, the subject S is placed on the top board 9a (step S206). For example, the subject S stands on the top board 9a according to the instruction of the technician, and waits in the instructed position.

[0114] Then, the acquiring function 16a acquires image-related information related to the local RF coil 5 (step S207). For example, the acquiring function 16a acquires, as the image-related information related to the local RF coil 5, information indicating the current attachment position where the local RF coil 5 is currently attached and the type of the local RF coil 5. Note that the process of step S207 is similar to the process of acquiring image-related information related to the local RF coil 5 in the process of step S104 shown in Fig. 2, and therefore a description thereof will be omitted.

[0115] Then, the selection function 16b selects the statistical information on the attachment position of the local RF coil 5 based on the image related information (step S208). Note that the process of step S208 is similar to the process of step S105 shown in FIG. 2, and therefore the description will be omitted.

[0116] Then, the output control function 16c displays the attachment position of the local RF coil 5 corresponding to the statistical information on the camera image (step S209). Note that the process of step S209 is similar to the process of step S106 shown in FIG. 2, so the description will be omitted.

[0117] Then, the local RF coil 5 is attached to the subject S (step S210). Note that the process of step S210 is similar to the process of step S107 shown in FIG. 2, and therefore a description thereof will be omitted.

[0118] In this way, the MRI apparatus 100 according to the second modification of the first embodiment can output a placement position for placing the subject S. This allows the technician to place the subject S on the tabletop 9a while referring to a suitable placement position for the subject S. As a result, the MRI apparatus 100 can improve the reproducibility of imaging without relying on the experience or skill of the technician.

[0119] The processing procedure explained in Fig. 7 is merely an example, and the embodiment is not limited thereto. For example, the processing procedure shown in Fig. 7 can be arbitrarily changed within a range that does not contradict the processing content. For example, when the mounting position of the local RF coil 5 is also displayed in the processing of step S205, the processing of steps S207 to S209 may not be executed.

[0120] (Modification 3 of the first embodiment) The output control function 16c can also notify information indicating that the subject S has been placed in the placement position.

[0121] For example, the output control function 16c judges whether the subject S is placed on the placement position. The judgment of whether the subject S is placed on the placement position is automatically performed by image recognition of the camera image I10. For example, the output control function 16c compares the current position of the subject S recognized from the camera image I10 with the placement position corresponding to the statistical information. Then, when the distance between the current position of the subject S and the placement position corresponding to the statistical information is within a predetermined range (within a threshold), the output control function 16c judges that the subject S is placed on the placement position. Then, when the output control function 16c judges that the subject S is placed on the placement position, for example, a message such as "The subject has been placed on a suitable placement position" is displayed on the gantry monitor 8b.

[0122] The output form of the information indicating that the subject S has been placed on the placement position is not necessarily limited to a message. For example, the output control function 16c may notify the information indicating that the subject S has been placed on the placement position by changing the color of the frame of the camera image I10 or the contour position image I30 or by hiding the contour position image I30.

[0123] In addition, the output form of the information indicating that the subject S has been placed in the placement position does not necessarily need to be notified by different display modes. For example, the output control function 16c may output a message saying "The subject has been placed in a suitable placement position" as a voice, or may notify by sound effects or vibration.

[0124] (Fourth Modification of the First Embodiment) In addition, the placement position of the subject S described in the second modified example of the first embodiment may be hidden as necessary. For example, when the subject S is placed at the placement position, or when an instruction from the operator is received, the output control function 16c hides the placement position.

[0125] For example, the output control function 16c judges whether or not the subject S is placed on the placement position. The judgment of whether or not the subject S is placed on the placement position is similar to the processing of the above-mentioned modified example 3, and therefore the explanation is omitted. Then, when the output control function 16c judges that the subject S is placed on the placement position, it makes the contour position image I30 invisible.

[0126] The determination of whether the subject S is placed on the placement position is not limited to image recognition, and may be performed by manual operation by a technician. For example, when the technician determines that the subject S is lying on the placement position, the technician inputs (such as pressing a predetermined button) that the position of the subject S has been confirmed. When this input is performed, the output control function 16c hides the placement position.

[0127] (Fifth Modification of the First Embodiment) In the above embodiment, a case where one local RF coil 5 is attached to the subject S has been described, but the embodiment is not limited to this. For example, in parallel imaging, which is one of the high-speed imaging methods, an MRI scan is performed by combining a body coil placed on the abdomen of the subject S and a spine coil placed on the back of the subject S. In this way, when multiple local RF coils 5 are attached to the subject S, the MRI apparatus 100 may output multiple attachment positions based on the relative positions of the multiple local RF coils 5.

[0128] For example, when multiple local RF coils 5 are attached to the subject S, the selection function 16b selects statistical information including the relative positions of the multiple local RF coils 5. In this case, the statistical information table stores the relative positions of the multiple local RF coils 5 for each piece of statistical information. The relative positions are defined by, for example, the distance and direction of the center positions (coordinates) of the respective local RF coils 5.

[0129] Then, the selection function 16b selects statistical information including the relative positions of the multiple local RF coils 5. For example, the selection function 16b selects statistical information corresponding to the information acquired by the acquisition function 16a from the multiple statistical information stored in the statistical information table. Here, the selected statistical information includes the relative positions of the multiple local RF coils 5 when multiple local RF coils 5 are attached to the subject S.

[0130] Then, the output control function 16c outputs a plurality of attachment positions at which the plurality of local RF coils 5 are attached to the subject S, based on the relative positions of the plurality of local RF coils 5.

[0131] Fig. 8 is a diagram showing a display example by the output control function 16c according to the modified example 5 of the first embodiment. For convenience of illustration, an image of the subject S depicted in the camera image I10 is omitted in Fig. 8.

[0132] 8, the output control function 16c displays a contour position image I22 and a contour position image I23 superimposed on a real-time camera image I10. The contour position image I22 and the contour position image I23 are indicators showing the attachment positions of different local RF coils 5. The positional relationship between the contour position image I22 and the contour position image I23 is defined based on the relative positions of the local RF coils 5.

[0133] In this way, when a plurality of local RF coils 5 are attached to the subject S, the MRI apparatus 100 can output a plurality of attachment positions based on the relative positions of the plurality of local RF coils 5.

[0134] Second Embodiment In the second embodiment, a case will be described in which a projector is used as an output form by the output control function 16c.

[0135] Fig. 9 is a diagram showing an example of the configuration of an MRI apparatus 100 according to the second embodiment. The MRI apparatus 100 according to the second embodiment has a configuration similar to that of the MRI apparatus 100 illustrated in Fig. 1, and further differs in that it includes a projector 18 and in part of the processing of the output control function 16c. Therefore, in the second embodiment, the differences from the first embodiment will be mainly described, and the same reference numerals as in Fig. 1 will be used to denote the same functions as those in the configuration described in the first embodiment, and description thereof will be omitted.

[0136] The projector 18 is a device that outputs (projects) an image onto the top plate 9a of the bed 9 under the control of the output control function 16c. The projector 18 is disposed at a position where the image can be projected onto the top plate 9a of the bed 9, such as the ceiling or wall of the imaging room or the gantry 8.

[0137] The output control function 16c outputs (projects) at least one of the attachment position of the local RF coil 5 and the position where the subject S is placed on the top board 9a of the bed 9 on which the subject S is placed.

[0138] Fig. 10 is a diagram showing an example of display by the output control function 16c according to the second embodiment. Fig. 10 illustrates a case where the coil attachment position and the subject position corresponding to the statistical information are projected onto the tabletop 9a.

[0139] In the example shown in Fig. 10, the output control function 16c projects a contour position image I41 and a contour position image I42 onto the tabletop 9a. Here, the contour position image I41 is a frame indicator showing the contour position of a person placed at an average subject position. The contour position image I42 is a frame indicator showing an average coil attachment position. The contour position image I41 and the contour position image I42 can be displayed by the same process as that described in the first embodiment, and therefore a description thereof will be omitted.

[0140] In this way, the output control function 16c can project the attachment position of the local RF coil 5 and the position where the subject S is placed by projection mapping.

[0141] 10 is merely an example, and the embodiment is not limited thereto. For example, the output control function 16c may project either the contour position image I41 or the contour position image I42.

[0142] Furthermore, when the subject S is placed on the tabletop 9a, the output control function 16c projects an image onto the tabletop 9a on which the subject S is placed. In this case, the image projected by the projector 18 is projected onto the tabletop 9a or the body surface of the subject S.

[0143] Moreover, the process described in the second embodiment can be appropriately combined with the processes described in the above embodiments and modifications.

[0144] (Third embodiment) In the third embodiment, a case will be described in which statistical information is generated from a camera image.

[0145] Fig. 11 is a diagram showing a configuration example of an MRI apparatus 100 according to the third embodiment. The MRI apparatus 100 according to the third embodiment has a configuration similar to that of the MRI apparatus 100 illustrated in Fig. 1, and further differs in that the processing circuitry 16 has a generating function 16d. Therefore, in the third embodiment, the differences from the first embodiment will be mainly described, and the same reference numerals as in Fig. 1 will be used to denote the same functions as those in the configuration described in the first embodiment, and description thereof will be omitted.

[0146] The generating function 16d generates statistical information based on the camera image I10. For example, the generating function 16d generates statistical information based on the camera image I10 captured just before the top plate 9a on which the subject S lies is inserted into the bore 8a, or the camera image I10 captured when the top plate 9a on which the subject S lies is ejected from the bore 8a after the scan. This is because the camera image I10 captured at these timings is considered to be an image that reflects the subject position and the coil mounting position in the actual scan.

[0147] Specifically, the generation function 16d calculates the central position of the subject S depicted in the camera image I10 and the central position of the local RF coil 5. Then, the generation function 16d updates the statistical information table stored in the storage circuitry 12 based on the calculated central position of the subject S and the central position of the local RF coil 5.

[0148] For example, a case will be described in which information indicating height "156 cm", posture "supine", scan site "abdomen", and coil type "abdominal coil" was acquired by the acquisition function 16a in the coil setting immediately before the camera image I10 to be processed was captured. In this case, the generation function 16d refers to the statistical information table in FIG. 4 and searches for statistical information corresponding to the information acquired by the acquisition function 16a. Then, the selection function 16b selects statistical information of statistical ID "001" from the statistical information table in FIG. 4. Then, the generation function 16d updates the statistical information of statistical ID "001" based on the center position of the subject S and the center position of the local RF coil 5 calculated from the camera image I10.

[0149] For example, the statistical information is associated with the coil attachment positions (coordinates) in the past several scans before the coil attachment positions are averaged. The generation function 16d then calculates an average value by adding the coil attachment positions calculated this time to the coil attachment positions in the past several scans. The generation function 16d then updates the statistical information of the statistical ID "001" using the newly calculated average value of the coil attachment positions. Note that the process of calculating the average value of the subject positions is similar to the process of calculating the average value of the coil attachment positions, and therefore will not be described.

[0150] In this way, the generating function 16d updates the statistical information based on the camera image I10, which allows the MRI apparatus 100 to update the statistical information table based on the latest scan.

[0151] The above description of the generating function 16d is merely an example, and the embodiment is not limited thereto. For example, the camera image I10 to be processed by the generating function 16d may be specified by a manual operation by an operator, instead of automatically acquiring the camera image I10 captured at the above timing.

[0152] In the above example, the case where only the statistical information table stored in the MRI device 100 (storage circuitry 12) is updated has been described, but the embodiment is not limited to this. For example, a statistical information table may be shared between MRI devices of the same model as the MRI device 100, and the shared statistical information table may be updated. The shared statistical information table may be stored in the storage circuitry 12, but is preferably stored in an external storage device such as a PACS.

[0153] Furthermore, sharing of statistical information tables is not limited to between MRI devices of the same model, but can be shared between any devices, such as between MRI devices of the same class (e.g., 1.5 Tesla) or between MRI devices from the same manufacturer (MRI device manufacturer), and it is also possible to update this shared statistical information table.

[0154] The generating function 16d does not necessarily have to be provided in the MRI apparatus 100. For example, the generating function 16d may be provided in an arbitrary external device connected to the MRI apparatus 100, and the statistical information table may be updated by acquiring a camera image I10 from the MRI apparatus 100.

[0155] (Other embodiments) In addition to the above-described embodiment, the present invention may be embodied in various different forms.

[0156] (Other medical imaging diagnostic equipment) For example, in the above embodiment and modified example, the processing functions according to the embodiment are applied to the MRI apparatus 100, but the embodiment is not limited thereto. For example, the present invention can be widely applied to medical image diagnostic apparatuses such as X-ray CT (Computed Tomography) apparatuses that perform imaging by placing a subject S on a bed, in addition to the MRI apparatus.

[0157] For example, each component of each device shown in the figure is a functional concept, and does not necessarily have to be physically configured as shown in the figure. In other words, the specific form of distribution and integration of each device is not limited to that shown in the figure, and all or a part of it can be functionally or physically distributed and integrated in any unit according to various loads, usage conditions, etc. Furthermore, each processing function performed by each device can be realized in whole or in any part by a CPU and a program analyzed and executed by the CPU, or can be realized as hardware using wired logic.

[0158] Furthermore, among the processes described in the above embodiments and modifications, all or part of the processes described as being performed automatically can be performed manually, or all or part of the processes described as being performed manually can be performed automatically by a known method. In addition, the information including the processing procedures, control procedures, specific names, various data and parameters shown in the above documents and drawings can be changed arbitrarily unless otherwise specified.

[0159] The mounting position output method described in the above embodiment and modified examples can be realized by executing a prepared mounting position output program on a computer such as a personal computer or a workstation. This mounting position output program can be distributed via a network such as the Internet. This mounting position output program can also be recorded on a non-transitory recording medium readable by a computer such as a hard disk, a flexible disk (FD), a CD-ROM, an MO, or a DVD, and executed by being read from the recording medium by a computer.

[0160] In the above embodiment and modified examples, "real time" means that each process is performed immediately each time data to be processed is generated. For example, the process of displaying an image in real time is not limited to the case where the time when the subject is imaged and the time when the image is displayed are completely the same, but includes the concept of the image being displayed with a slight delay depending on the time required for each process such as image processing.

[0161] According to at least one of the embodiments described above, it is possible to improve the reproducibility of imaging.

[0162] Although some embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations of embodiments can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents as described in the claims, as well as in the scope and spirit of the invention. [Explanation of symbols]

[0163] 100 MRI machine 16 Processing circuit 16a Acquisition Function 16b Selection Function 16c Output control function 16d generation function

Claims

1. A memory circuit that stores a plurality of statistical information classified according to at least one of a body type of a first subject, a posture of the first subject, a position of the first subject, an attachment position of a first RF (Radio Frequency) coil attached to the first subject, a type of the first RF coil, identification information of the first RF coil, and a scan site; an acquisition unit that acquires, from an image of a second subject captured by an optical imaging device, first information indicating at least one of a body type of the second subject, a posture of the second subject, and a position of the second subject, and second information indicating at least one of an attachment position of a second RF coil attached to the second subject, a type of the second RF coil, identification information of the second RF coil, and a scan site; a selection unit that, when the first information is acquired, selects statistical information corresponding to the first information from the storage circuitry, and, when the second information is acquired, selects statistical information corresponding to the second information from the storage circuitry; an output control unit that outputs an image relating to a method of attaching the second RF coil to the second subject based on the selected statistical information; A magnetic resonance imaging apparatus comprising:

2. The acquisition unit acquires scan conditions for scanning the second subject, the selection unit further selects, from the storage circuitry, statistical information corresponding to the scan condition.

2. A magnetic resonance imaging apparatus according to claim 1.

3. the acquiring unit acquires, as the scan condition, information indicating at least one of a scan site, a type of the second RF coil, and identification information of the second RF coil; the selection unit selects, as the statistical information, statistical information corresponding to information indicating at least one of the scan site, the type of the second RF coil, and identification information of the second RF coil.

3. A magnetic resonance imaging apparatus according to claim 2.

4. the output control unit causes a display unit to display an image relating to a method of attaching the second RF coil corresponding to the statistical information.

4. The magnetic resonance imaging apparatus according to claim 1,

5. the output control unit causes an image relating to the attachment method of the second RF coil corresponding to the statistical information to be superimposed on an image of the second subject or a schematic image of a human body.

5. A magnetic resonance imaging apparatus according to claim 4.

6. the output control unit notifies information indicating that the second RF coil is attached to the attachment position of the first RF coil when the attachment position of the first RF coil is selected as the statistical information.

6. A magnetic resonance imaging apparatus according to claim 1.

7. the selection unit selects, based on the first information, statistical information on a placement position at which the first subject is to be placed, as a position of the first subject; The output control unit outputs an image showing the placement position as an image related to a method of attaching the second RF coil.

7. A magnetic resonance imaging apparatus according to claim 1.

8. The output control unit notifies information indicating that the second subject has been placed at the placement position.

8. A magnetic resonance imaging apparatus according to claim 7.

9. the output control unit, when the second subject is placed at the placement position, or when an instruction from an operator is received, does not display the placement position.

9. A magnetic resonance imaging apparatus according to claim 7 or 8.

10. the selection unit selects statistical information including relative positions of the second RF coils when a plurality of second RF coils are attached to the second subject; the output control unit causes an output of images relating to a plurality of attachment methods for attaching a plurality of second RF coils to the second subject based on the relative positions.

10. A magnetic resonance imaging apparatus according to claim 1.

11. the output control unit outputs an image relating to a mounting method of the second RF coil to a top board of a bed on which the second subject is placed.

11. A magnetic resonance imaging apparatus according to claim 1.

12. A generating unit that generates the statistical information based on the image.

12. A magnetic resonance imaging apparatus according to claim 1.

13. The generating unit generates the statistical information based on an image taken immediately before the top plate on which the second subject lies is inserted into the bore, or an image taken when the top plate on which the second subject lies is ejected from the bore after scanning.

13. A magnetic resonance imaging apparatus according to claim 12.

14. from an image of a second subject captured by an optical imaging device, first information indicating at least one of a body type of the second subject, a posture of the second subject, and a position of the second subject, and at least one of second information indicating an attachment position of a second RF (Radio Frequency) coil attached to the second subject, a type of the second RF coil, identification information of the second RF coil, and a scan site; When the first information is acquired, statistical information corresponding to the first information is selected from a memory circuit that stores a plurality of pieces of statistical information classified according to at least one of a body type of a first subject, a posture of the first subject, a position of the first subject, a mounting position of a first RF (Radio Frequency) coil attached to the first subject, a type of the first RF coil, identification information of the first RF coil, and a scan site, and when the second information is acquired, statistical information corresponding to the second information is selected from the memory circuit; outputting an image relating to a method of attaching the second RF coil to the second subject based on the selected statistical information; The mounting position output method includes:

15. from an image of a second subject captured by an optical imaging device, first information indicating at least one of a body type of the second subject, a posture of the second subject, and a position of the second subject, and at least one of second information indicating an attachment position of a second RF (Radio Frequency) coil attached to the second subject, a type of the second RF coil, identification information of the second RF coil, and a scan site; When the first information is acquired, statistical information corresponding to the first information is selected from a memory circuit that stores a plurality of pieces of statistical information classified according to at least one of a body type of a first subject, a posture of the first subject, a position of the first subject, a mounting position of a first RF (Radio Frequency) coil attached to the first subject, a type of the first RF coil, identification information of the first RF coil, and a scan site, and when the second information is acquired, statistical information corresponding to the second information is selected from the memory circuit; outputting an image relating to a method of attaching the second RF coil to the second subject based on the selected statistical information; An installation position output program that causes a computer to execute each process.

Images