JP5238156B2 - Magnetic resonance imaging apparatus and high frequency coil selection method in the apparatus - Google Patents

Description

The present invention relates to a magnetic resonance imaging (MRI) apparatus that acquires a magnetic resonance (MR) image of a subject using a magnetic resonance phenomenon, and a method for selecting a high-frequency coil in the apparatus.

  In the magnetic resonance imaging apparatus, there is a technique in which a plurality of high-frequency coils (RF coils) are arranged on the abdomen of a subject and the subject is imaged while being moved.

An MRI apparatus that selectively uses a plurality of RF coils to capture an image is known from, for example, Patent Document 1.
JP 2003-334177 A

  In the case of the technique for imaging while moving the subject as described above, if all of the MR signals output from each of the plurality of RF coils are always used for reconstruction, an increase in time for reconstruction or There has been a risk of increasing the number of images obtained and reducing the efficiency of diagnosis.

  In order to avoid the above problems, it is desirable to select an RF coil located in the imaging region from among a plurality of RF coils and use only the MR signal output from the RF coil for reconstruction. However, since the RF coil arranged in the upper abdomen has a high degree of freedom in the installation position, it is difficult for the MRI apparatus to grasp the installation position of the RF coil. In order to specify the installation position in advance, the operator's Since setting is required, the burden on the operator increases.

  The present invention has been made in consideration of such circumstances, and an object of the present invention is to enable automatic detection of the installation position of the RF coil.

In the magnetic resonance imaging apparatus according to the first aspect of the present invention, a top plate for placing a subject to be imaged and a plurality of positions at which installation positions of high-frequency coils that can be attached to and detached from the top plate are different. A plurality of positioning sections determined by the positioning section, a determination section for determining a relative position of the high-frequency coil positioned by the positioning section with respect to the top plate, and a plurality of the high-frequency coils positioned by the plurality of positioning sections. And a selection unit that selects one of the plurality of high frequency coils to be used for imaging based on the position determined by the determination unit for each of the plurality of high frequency coils and the position of the top plate .

A magnetic resonance imaging apparatus according to a second aspect of the present invention includes a couch that has a couch on which a subject is placed and that slides the couch in a first direction in order to move the subject in the body axis direction. An application unit that applies a gradient magnetic field and a high-frequency pulse to the subject sent into the static magnetic field by the bed; and a magnetism emitted from the subject in response to the application of the gradient magnetic field and the high-frequency pulse. A plurality of high-frequency coils for detecting resonance signals; a plurality of positioning parts for determining the installation positions of the plurality of high-frequency coils at different positions; and the plurality of high-frequency coils positioned by the positioning parts. A determination unit that determines a relative position with respect to the top plate, and a position that is determined by the determination unit for each of the plurality of high-frequency coils. Based on the position of the top plate, and a selection section to select one to be used for imaging from the plurality of radio frequency coils.

The method according to the third aspect of the present invention includes a plurality of positions in which a top plate for placing a subject to be imaged and a high-frequency coil detachable from the top plate are set at a plurality of different positions. A high-frequency coil selection method in a magnetic resonance imaging apparatus comprising: a positioning unit configured to determine a relative position of the high-frequency coil positioned by the positioning unit with respect to the top plate; When the plurality of high-frequency coils are positioned, the one used for imaging is selected from the plurality of high-frequency coils based on the position determined for each of the plurality of high-frequency coils and the position of the top plate .

The method according to the fourth aspect of the present invention includes a top plate on which a subject to be imaged is placed, and slides the top plate in a first direction to move the subject in the body axis direction. A bed, an application unit that applies a gradient magnetic field and a high-frequency pulse to the subject sent into the static magnetic field by the bed, and a radiation emitted from the subject in response to the application of the gradient magnetic field and the high-frequency pulse a plurality of the high-frequency coil, a method of selecting the radio frequency coil in the magnetic resonance imaging apparatus having a plurality of positioning portions for determining the installation position of the plurality of RF coils in a plurality of different positions each for detecting magnetic resonance signals, respectively a is the position relative to the top plate of said plurality of high-frequency coils positioned in the positioning portion respectively determined, the Based on the positions determined for each of the number of RF coils and the position of the top plate, to select one to be used for imaging from the plurality of radio frequency coils.

  According to the present invention, the installation position of the RF coil can be automatically detected.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram of an MRI apparatus 100 according to this embodiment.

  The MRI apparatus 100 includes a static magnetic field generation unit 1, a gradient magnetic field generation unit 2, a transmission / reception unit 3, a calculation / storage unit 4, a bed unit 5, a radio frequency (RF) coil unit 6, a position detection unit 7, a user interface unit 8, and a control. Part 9 is provided.

  The static magnetic field generation unit 1 further includes a main magnet 11 and a static magnetic field power supply 12. For example, a superconducting magnet is used as the main magnet 11. The static magnetic field power supply 12 supplies a current to the main magnet 11. The main magnet 11 forms a strong static magnetic field.

  The gradient magnetic field generator 2 further includes a gradient magnetic field coil 21 and a gradient magnetic field power source 22. The gradient magnetic field coil 21 forms gradient magnetic fields in the X, Y, and Z axis directions orthogonal to each other. The gradient magnetic field power supply 22 supplies a current to the gradient magnetic field coil 21. The gradient magnetic field coil 21 superimposes a gradient magnetic field on a static magnetic field. A control signal is supplied to the gradient magnetic field power source 22 by the control unit 9, and the current supplied to the gradient magnetic field coil 21 is changed accordingly. Thereby, the gradient magnetic field generator 2 appropriately forms a gradient magnetic field for arbitrarily encoding the static magnetic field space. That is, by changing the pulse current supplied from the gradient magnetic field power source 22 to the X, Y, Z axis gradient magnetic field coil 21 based on the gradient magnetic field control signal, the gradient magnetic fields in the X, Y, Z axis directions are changed. A gradient magnetic field for slice selection, a gradient magnetic field for phase encoding, and a gradient magnetic field for readout (frequency encoding) that are synthesized and orthogonal to each other are set in arbitrary directions.

  The main magnet 11 and the gradient magnetic field coil 21 are accommodated in a gantry having a cavity. The center of the static magnetic field is located in the cavity.

  The transceiver unit 3 further includes a transmitter 31 and a receiver 32. The transmitter 31 includes a reference signal generator, a modulator, a power amplifier, and the like, and modulates a reference signal having the same frequency as the magnetic resonance frequency (Larmor frequency) determined according to the strength of the static magnetic field with a selective excitation waveform. By doing so, a high-frequency transmission signal is obtained. The transmitter 31 supplies the obtained transmission signal to the RF coil unit 6. The receiver 32 performs A / D conversion after performing signal processing such as intermediate frequency conversion, phase detection, and filtering on the MR signal output from the RF coil unit 6. Further, the receiver 32 includes a 90 ° phase shifter for performing phase alignment when the MR signals are two MR signals generated by a QD type volume coil and having phases different from each other by 90 °. .

  The calculation / storage unit 4 further includes a high-speed calculation circuit 41 and a storage circuit 42. The storage circuit 42 further includes an MR signal storage circuit 421 and an image data storage circuit 422. The MR signal storage circuit 421 stores the MR signal digitized by the receiver 32. The image data storage circuit 422 stores the image data generated by the high speed arithmetic circuit 41. The high-speed arithmetic circuit 41 performs reconstruction processing by two-dimensional Fourier transform on the MR signal stored in the MR signal storage circuit 421 to generate real space image data.

  The bed unit 5 further includes a top plate 51 and a moving mechanism unit 52. The shape of the top plate 51 is an elongated thin plate shape. The top 51 is instructed to be slidable in the longitudinal direction (the directions of arrows A and B in FIG. 1) by the base portion of the bed. The subject P is placed on the top surface of the top plate 51 such that the body axis direction substantially coincides with the longitudinal direction. Accordingly, the top 51 conveys the subject P in the body axis direction. Then, the top plate 51 arbitrarily sets the imaging position with respect to the subject P by sending the subject P from outside the static magnetic field into the static magnetic field and changing the position of the subject P with respect to the static magnetic field. The movement mechanism part 52 moves the top plate 51 in the longitudinal direction.

  The RF coil unit 6 further includes an RF coil 61 and a support portion 62. The RF coil 61 transmits an RF pulse based on the transmission signal supplied from the transmitter 31. The RF coil 61 detects an MR signal emitted from the subject P and sends the MR signal to the receiver 32. The support portion 62 is attached to the top plate 51 and supports the RF coil 61 so as to be positioned above the top plate 51. The RF coil 61 can be attached to and detached from the support portion 62. Further, the support part 62 is slidable in the longitudinal direction of the top plate 51.

  The position detection unit 7 further includes a coil position detection unit 71 and a support body position detection unit 72. The coil position detector 71 detects the position where the RF coil 61 is mounted. The support body position detection unit 72 detects the position of the support unit 62.

  The user interface unit 8 further includes an input unit 81 and a display unit 82. The input unit 81 includes various input devices such as a switch, a keyboard, and a mouse on the console. The input unit 81 acquires information and instructions input by the operator. The information acquired by the input unit 81 includes, for example, various information related to the subject P, information related to imaging conditions such as imaging methods and pulse sequences, and display conditions. The instruction acquired by the input unit 81 is, for example, an instruction to start shooting, an instruction related to the movement of the top 51, or the like. The display unit 82 includes a video memory, a conversion circuit, and a monitor. When the image data stored in the image data storage circuit 422 is supplied to the display unit 82 via the control unit 9, the display unit 82 stores the image data in the video memory. Then, the image data and the accompanying information such as the subject information input from the input unit 81 are combined in the video memory. Image data created in the video memory by this synthesis is converted into a television signal and D / A converted by a conversion circuit to be converted into an image signal, which is then supplied to a monitor. The monitor displays an image represented by the image signal. As a monitor, a cathode-ray tube (CRT) or a liquid crystal display (LCD) can be used.

  The control unit 9 further includes a main control circuit 91, a sequence control circuit 92, and a moving mechanism control circuit 93. The main control circuit 91 includes a CPU and a storage circuit, and controls the MRI apparatus 100 in an integrated manner. The storage circuit of the main control circuit 91 stores information related to the shooting conditions and display conditions acquired by the input unit 81. The CPU of the main control circuit 91 supplies pulse sequence information to the sequence control circuit 92 based on the above information stored in the storage circuit. The pulse sequence information is, for example, information related to the magnitude of the current supplied to the gradient magnetic field coil 21, the level of the transmission signal, the application time, the application timing, and the like. The sequence control circuit 92 includes a CPU and a storage circuit, and controls the gradient magnetic field power source 22, the transmitter 31, and the receiver 32 according to the pulse sequence information. The moving mechanism control circuit 93 includes a CPU and a storage circuit, generates a control signal for moving the top plate 51, and supplies this control signal to the moving mechanism unit 52.

  2 and 3 are diagrams showing a detailed configuration of the RF coil unit 6.

  The support part 62 includes a first support body 62a and a second support body 62b shown in FIG. The first and second supports 62 a and 62 b are slidable in the longitudinal direction of the top plate 51 by being guided by grooves 51 a and 51 b formed in the longitudinal direction of the top plate 51. The grooves 51 a and 51 b are parallel to each other with a sufficient distance to place the subject P in the direction intersecting the longitudinal direction of the top plate 51.

  As shown in FIGS. 2 and 3, the RF coil unit 6 includes a socket 63, a recess 64, connecting members 65 a and 65 b, a plug 66, and a fitting member 67 in addition to the RF coil 61 and the support portion 62.

  A plurality of sockets 63 are provided on the first support body 62 a in a state of being arranged along the longitudinal direction of the top plate 51. The same number of recesses 64 as the sockets 63 are provided in the first support 62a in a state of being arranged so as to form pairs with the sockets 63, respectively. In the present embodiment, three pairs of sockets 63 and recesses 64 are provided, but this number may be arbitrary.

  The connecting members 65a and 65b are, for example, flexible belt-shaped members. One end of the connecting member 65 a is attached to the RF coil 61, and the other end is attached to the plug 66. One end of the connecting member 65 b is attached to the RF coil 61, and the other end is attached to the fitting member 67.

  The plug 66 can be inserted into and removed from the socket 63. Electrical wiring is provided so that the RF coil 61 is electrically connected to the transmitter 31 and the receiver 32 when the plug 66 is inserted into the socket 63. Further, when the plug 66 is attached to the socket 63, the plug 66 is fitted into the socket 63. That is, the socket 63 and the plug 66 constitute a connector for electrically connecting the RF coil 61 to the main body side of the MRI apparatus and mechanically fixing it.

  The fitting member 67 can be inserted into and removed from the recess 64. When the fitting member 67 is inserted into the recess 64, the fitting member 67 is fitted into the recess 64. Thus, the concave portion 64 and the fitting member 67 constitute a fixing portion for mechanically fixing the RF coil 61 to the main body side of the MRI apparatus.

  Thus, by inserting the plug 66 into the socket 63 and inserting the fitting member 67 into the recess 64, one RF coil 61 is assembled to the pair of socket 63 and recess 64. The relative positions of the RF coil 61 assembled in this way with respect to the first and second supports 62a and 62b are such that the plug 66 and the fitting member 67 are fitted in the socket 63 and the recess 64, respectively. It is defined with respect to the longitudinal direction of the top plate 51. That is, it is possible to arbitrarily mount the RF coil 61 at each of the three mounting positions formed by the socket 63 and the recess 64 that form a pair.

  The socket 63 has a function of outputting a first detection signal indicating whether or not the plug 66 is inserted to the coil position detection unit 71. This function is realized by, for example, a configuration in which an electrical contact that is closed when the plug 66 is inserted is provided in the socket 63 and a detection signal including ID information of the socket 63 is output when the electrical contact is closed. it can.

  The first support body 62 a has a function of outputting a second detection signal representing a relative position with respect to the top plate 51 to the support body position detection unit 72. This function can be realized, for example, by using a known position detection sensor.

  Next, the operation of the MRI apparatus configured as described above will be described.

  In a state where the top plate 51 is pulled out from the gantry and no RF coil 61 is attached, the subject P can be easily placed on the top plate 51. After placing the subject P on the top board 51, the operator mounts an arbitrary number of RF coils 61 according to the part to be imaged of the subject P. At this time, for example, if the plug 66 is first inserted into the socket 63, the relative positional relationship between the RF coil 61 and the subject P can be finely adjusted by slightly moving the first support 62a. it can. If the first support body 62a can move a distance of about ½ of the arrangement pitch of the sockets 63, the degree of freedom of the fine adjustment is high. Subsequently, the fitting member 67 can be easily inserted into the recess 64 by slightly moving the second support 62 b so that the recess 64 faces the socket 63 into which the plug 66 has been inserted. Of course, it is also possible to insert the plug 66 into the socket 63 after the fitting member 67 is inserted into the recess 64 first.

  Thus, the first detection signal is output to the coil position detection unit 71 from the socket 63 in which the plug 66 is inserted in order to mount the RF coil 61. The coil position detector 71 detects the mounting position where the RF coil 61 is mounted based on the ID information included in the input first detection signal. The coil position detection unit 71 sends coil position information representing the detection result to the main control circuit 91.

  On the other hand, the support body position detection part 72 detects the position of the support body 62a based on the 2nd detection signal output from the 1st support body 62a. The support body position detection unit 72 sends support body position information representing the detection result to the main control circuit 91.

  Here, based on the detected coil position information of the plurality of RF coils 61, the main control circuit 91 selects an RF coil 61 that can obtain sufficient sensitivity in a desired imaging region, and starts imaging an MR image. . Based on the RF signal obtained by the RF coil 61, the high-speed arithmetic circuit 41 reconstructs the MR image. The reconstructed MR image is displayed on the display unit 82.

  When it is determined that the RF coil 61 having sufficient sensitivity is not present or insufficient, for example, the photographing operation is canceled, and the same procedure is performed based on the coil position information of the other RF coils 61. Sensitivity is determined, and an MR image is captured in a desired imaging region.

  Alternatively, the main control circuit 91 determines a relative position of the mounted RF coil 61 with respect to the top plate 51 based on the coil position information and the support body position information. When the main control circuit 91 performs imaging while moving the top plate 51, the main control circuit 91 appropriately selects the position of the top plate 51 and the relative position of the mounted RF coil 61 with respect to the top plate 51. It is also possible to control the RF coil 61 to be used for imaging. The suitable RF coil 61 is preferably an RF coil 61 located closest to the center of the static magnetic field.

  As described above, according to the present embodiment, the RF coil 61 can be arbitrarily attached to a plurality of attachable positions each formed by the pair of sockets 63 and the recesses 64. The installation position of the attached RF coil 61 is detected based on which of the plurality of sockets 63 the plug 66 is inserted in order to attach the RF coil 61. Thus, in the MRI apparatus of this embodiment, it is possible to accurately grasp the installation position of the RF coil 61 that is arbitrarily attached. Then, by considering the installation position of the RF coil 61 and selectively using an appropriate RF coil 61 for imaging, processing for reconstruction is reduced and unnecessary images can be obtained. It is possible to perform efficient imaging with no increase in the burden on the operator.

  This embodiment can be variously modified as follows.

  The structure for positioning the RF coil 61 is not limited to that shown in the above embodiment, and can be changed to other various positioning structures. For example, instead of the recess 64 and the fitting member 67, a socket and a plug may be provided. For example, you may make it not provide either the socket 63 and the plug 66, the recessed part 64, and the fitting member 67. FIG. When the socket 63 and the plug 66 are not provided, the RF coil 61 and the transmission / reception unit 3 are electrically connected using a separate cable or the like. The socket 63 may be attached to the RF coil 61 side, and the plug 66 may be provided on the top plate 51 side. The recess 64 may be attached to the RF coil 61 side, and the fitting member 67 may be provided on the top plate 51 side.

  The socket 63 and the recess 64 may be provided directly on the top plate 51 without providing the first and second supports 62a and 62b. The first and second supports 62a and 62b may be fixed to the top plate 51. In these cases, the support body position detector 72 can be omitted. In the main control circuit 91, it is also possible to determine the relative position of the mounted RF coil 61 with respect to the top plate 51 based only on the coil position information.

  The function of outputting the first detection signal to the coil position detection unit 71 can be provided in the concave portion 64, the first support body 62a, the second support body 62b, the top plate 51, or the like.

  The first detection signal may be input to the coil position detection unit 71 in parallel, and the coil position detection unit 71 may detect the position of the RF coil 61 based on which first detection signal is input. Is possible. In this case, it is not necessary to include ID information in the first detection signal.

  The RF coil 61 has a function of outputting ID information for identifying each RF coil 61 and ID information for identifying the type of the RF coil 61, and this ID information is included in the first detection signal. May be. In this case, a plurality of types of RF coils 61 having different relative positions with respect to the plug 66 of the coil element of the RF coil 61 can be mounted, and the position of the coil element in the mounted RF coil 61 is plugged. It is possible to accurately detect the difference relative to the position 66. Moreover, when the RF coil 61 incorporating a plurality of coil elements is inserted, it is also possible to detect the individual positions of the coil elements.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment.

1 is a block diagram of an MRI apparatus according to an embodiment of the present invention. The figure which shows the detailed structure of the RF coil unit in FIG. The figure which shows the detailed structure of the RF coil unit in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Static magnetic field generation | occurrence | production part, 2 ... Gradient magnetic field generation | occurrence | production part, 3 ... Transmission / reception part, 4 ... Calculation / storage part, 5 ... Sleeper unit, 6 ... High frequency (RF) coil unit, 7 ... Position detection unit, 8 ... User interface Unit: 9 ... Control unit, 11 ... Main magnet, 12 ... Static magnetic field power supply, 21 ... Gradient magnetic field coil, 22 ... Gradient magnetic field power supply, 31 ... Transmitter, 32 ... Receiver, 41 ... High speed arithmetic circuit, 42 ... Memory circuit 51 ... Top plate, 51a, 51b ... Groove, 52 ... Moving mechanism part, 61 ... RF coil, 62 ... Support part, 62a ... First support, 62b ... Second support, 63 ... Socket, 64 ... Recesses, 65a, 65b ... connecting member, 66 ... plug, 67 ... fitting member, 71 ... coil position detector, 72 ... support position detector, 81 ... input unit, 82 ... display unit, 91 ... main control circuit, 92 ... Sequence control circuit, 93 ... Transfer Mechanism control circuit, 100 ... MRI apparatus 421 ... signal storage circuit, 422 ... image data storage circuit.

Claims (23)

A top plate for placing a subject to be imaged;
A plurality of positioning portions that determine the installation positions of the high-frequency coils that can be attached to and detached from the top plate at a plurality of different positions, respectively.
A determination unit for determining a relative position of the high-frequency coil positioned by the positioning unit with respect to the top plate;
When the plurality of high-frequency coils are positioned by the plurality of positioning units, the plurality of high-frequency coils are determined based on the position determined by the determination unit and the position of the top plate for each of the plurality of high-frequency coils. A magnetic resonance imaging apparatus, comprising: a selection unit that selects an image to be used for imaging from among them . The positioning portion includes a first member and a second member that are fitted together to electrically and mechanically connect the high-frequency coil to the top plate, and for fixing the high-frequency coil to the top plate. magnetic resonance imaging apparatus according to claim 1, characterized in that at least one of the one of the third and fourth members to be fitted to each other.   One of the first and second members and one of the third and fourth members are arranged to face each other across the body axis of the subject placed on the top plate The magnetic resonance imaging apparatus according to claim 2. Wherein the relative top plate is movably arranged in the body axis direction of the subject, further comprising a support you support the positioning unit,
The determination unit, a magnetic resonance imaging apparatus according to claim 1, characterized in that to determine the relative position in consideration of the position of the support relative to the top plate of the high-frequency coil.   The magnetic resonance imaging apparatus according to claim 1, further comprising the high-frequency coil. The positioning portion includes at least one of one of the first and second members and one of the third and fourth members,
The magnetic resonance imaging apparatus according to claim 5, wherein a member that fits with a member included in the positioning portion among the first to fourth members is attached to the high-frequency coil.   The magnetic resonance imaging apparatus according to claim 6, wherein at least one of the first to fourth members is attached to the high-frequency coil via a belt-like connecting member. A plurality of generators respectively corresponding to the plurality of positioning units, wherein the generator corresponding to the positioning unit used for positioning of the high-frequency coil identifies the corresponding positioning unit ; Generate an identification signal,
And the said judgment part judges the said positioning part currently used for positioning of the said high frequency coil based on the identification signal which the said generation | occurrence | production part produces | generates, and is relative to the said top plate of the position defined by the said positioning part The magnetic resonance imaging apparatus according to claim 1, wherein a correct position is determined . A plurality of generators respectively corresponding to the plurality of positioning units, wherein the generator corresponding to the positioning unit used for positioning of the high-frequency coil identifies the corresponding positioning unit; Generating an identification signal for identifying the high-frequency coil to be positioned by the corresponding positioning unit;
And the said judgment part discriminate | determines the said positioning part and the said high frequency coil currently used for positioning of the said high frequency coil based on the identification signal which the said generation | occurrence | production part produces | generates, and it incorporates in the said high frequency coil based on this The magnetic resonance imaging apparatus according to claim 1, wherein a relative position of the at least one coil element to the top plate is determined . The determination unit, when said RF coil is more built the coil elements, the magnetic resonance according to the relative position with respect to the top plate of the plurality of coil elements to claim 9, wherein the determining respectively Imaging device. A couch having a top plate on which the subject is placed and sliding the top plate in a first direction to move the subject in the body axis direction;
An application unit that applies a gradient magnetic field and a high-frequency pulse to the subject sent into the static magnetic field by the bed;
A plurality of high-frequency coils for detecting magnetic resonance signals emitted from the subject in response to the application of the gradient magnetic field and the high-frequency pulse;
A plurality of positioning portions that determine the installation positions of the plurality of high-frequency coils at a plurality of different positions ;
A determination unit that determines a relative position of each of the plurality of high-frequency coils positioned by the positioning unit with respect to the top plate;
And a selection unit that selects one of the plurality of high-frequency coils to be used for imaging based on the position determined by the determination unit and the position of the top plate for each of the plurality of high-frequency coils. Magnetic resonance imaging apparatus. The positioning portion includes a first member and a second member that are fitted together to electrically and mechanically connect the high-frequency coil to the top plate, and for fixing the high-frequency coil to the top plate. includes at least one of either the third and fourth members to be fitted to each other,
The magnetic resonance imaging apparatus according to claim 11, wherein a member that fits with a member included in the positioning portion among the first to fourth members is attached to the high-frequency coil. The positioning portion includes both one of the first and second members and one of the third and fourth members,
The magnetic resonance imaging apparatus according to claim 12, wherein the first or second member and the third or fourth member included in the positioning unit are arranged at substantially the same pitch.   One of the first and second members and one of the third and fourth members are arranged to face each other across the body axis of the subject placed on the top plate The magnetic resonance imaging apparatus according to claim 12. The selection unit determines a relative position of each of the plurality of high frequency coils with respect to the center of the static magnetic field based on the position determined by the determination unit and the position of the top plate for each of the plurality of high frequency coils. The magnetic resonance imaging apparatus according to claim 11 , wherein among the plurality of high-frequency coils, the one closest to the center of the static magnetic field is selected for use in imaging. Wherein the relative top plate is movably arranged in the body axis direction of the subject, further comprising a support you support the positioning unit,
The determination unit, a magnetic resonance imaging apparatus according to claim 15, characterized in that to determine the relative position in consideration of the position of the support relative to the top plate of the high-frequency coil.   13. The magnetic resonance imaging apparatus according to claim 12, wherein at least one of the first to fourth members is attached to the high-frequency coil via a belt-like connecting member. An identification signal that further includes a plurality of generation units respectively corresponding to the plurality of positioning units, and that the generation unit corresponding to the positioning unit used for positioning the high-frequency coil identifies the corresponding positioning unit Occur and
And said determination unit, a magnetic resonance imaging apparatus according to claim 11, characterized in that to determine the positioning portion is used for positioning of the high-frequency coil on the basis of the identification signal wherein the generating unit generates . A plurality of generators respectively corresponding to the plurality of positioning units, wherein the generator corresponding to the positioning unit used for positioning of the high-frequency coil identifies the corresponding positioning unit; Generating an identification signal for identifying the high-frequency coil to be positioned by the corresponding positioning unit;
And the said judgment part discriminate | determines the said positioning part and the said high frequency coil currently used for positioning of the said high frequency coil based on the identification signal which the said generation | occurrence | production part produces | generates, and it incorporates in the said high frequency coil based on this The magnetic resonance imaging apparatus according to claim 11, wherein a relative position of the at least one coil element to the top plate is determined . The determination unit, when said RF coil is more built the coil elements, the magnetic resonance according to the relative position with respect to the top plate of the plurality of coil elements to claim 19, wherein the determining respectively Imaging device. The selection unit determines a relative position of each of the plurality of high frequency coils with respect to the center of the static magnetic field based on the position determined by the determination unit and the position of the top plate for each of the plurality of high frequency coils. 2. The magnetic resonance imaging apparatus according to claim 1, wherein among the plurality of high-frequency coils, the one closest to the center of the static magnetic field is selected for use in imaging. A magnetic resonance imaging apparatus comprising: a top plate for placing a subject to be imaged; and a plurality of positioning portions that determine installation positions of high-frequency coils that can be attached to and detached from the top plate at a plurality of different positions. In the method of selecting the high frequency coil in
Determining a relative position of the high-frequency coil positioned by the positioning unit with respect to the top plate;
When the plurality of high-frequency coils are positioned by the plurality of positioning units, imaging is performed from among the plurality of high-frequency coils based on the position determined for each of the plurality of high-frequency coils and the position of the top plate. A method characterized by selecting what to use . A couch having a couch on which a subject to be imaged is placed, and a couch that slides the couch in a first direction to move the cue in the body axis direction, and the couch is fed into a static magnetic field by the couch An application unit for applying a gradient magnetic field and a high-frequency pulse to the subject, and a plurality of magnetic resonance signals radiated from the subject in response to the application of the gradient magnetic field and the high-frequency pulse. a high-frequency coil, in the selection methods of the radio frequency coil in the magnetic resonance imaging apparatus having a plurality of positioning portions for determining the installation position of the plurality of RF coils in a plurality of different positions, respectively,
Determining a relative position of each of the plurality of high-frequency coils positioned by the positioning unit with respect to the top plate;
A method for selecting one of the plurality of high-frequency coils to be used for imaging based on the position determined for each of the plurality of high-frequency coils and the position of the top plate .

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