JP2019092935A - Magnetic resonance imaging device and fastener thereof - Google Patents

Abstract

To provide a magnetic resonance imaging device capable of feeding power to an RF reception coil which sends an NMR signal by radio communication, regardless of an imaging region and a posture of a test object.SOLUTION: A fastener 403 for fixing a test object to a table 401 has a power feeding part 415 for supplying power to a reception coil unit. The reception coil unit has a power reception part 408 for receiving power from the power feeding part. For example, the reception coil unit is mounted on the test object, the fastener is wound to the test object from an upper side of the reception coil unit, for fixing the test object to a top board 402 and fixing the reception coil unit to the test object, and in the state, the power is supplied.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a radio frequency (hereinafter referred to as RF) coil of a magnetic resonance imaging (hereinafter referred to as MRI) apparatus, and more particularly to power supply to an RF receiving coil.

  An MRI apparatus arranges a subject in a uniform static magnetic field space in a shield room, applies a gradient magnetic field and a high frequency magnetic field for excitation, and generates NMR signals generated using nuclear magnetic resonance (NMR) phenomena as RF signals. It is an apparatus which receives by a coil and images an inspection object. The MRI apparatus includes, in a gantry, a magnet for generating a static magnetic field, a gradient magnetic field generating coil for generating a gradient magnetic field, and an RF irradiation coil for generating a high frequency magnetic field for excitation.

  A subject is placed on the top of a table and an RF receiving coil is attached. At this time, the RF receiving coil is fixed to the subject using a fixture for fixing the subject to the top plate. The subject is placed in the gantry with the table. Thus, by fixing the RF receiving coil to the subject, the image quality of the image obtained by MRI can be improved.

  Generally, an NMR signal generated from a subject is received by an RF receiving coil, amplified by a preamplifier in the RF receiving coil, and then separated from the table as it is as an analog signal via wiring such as a coaxial cable. It is widely known that the structure is transmitted to a receiver located at a different position and subjected to A / D conversion at the receiver.

  In recent years, there is also known a structure in which a receiver for A / D conversion is disposed in an RF receiving coil, and an NMR signal is digitized in the RF receiving coil and then transmitted to a computer disposed outside the gantry. . As a result, compared to the case of using an analog coaxial cable, it is possible to suppress the noise mixing in the transmission path and the crosstalk between the reception channels, so that it is possible to improve the S / N ratio and achieve multiple channels. In addition, the cable connected to the RF receiving coil can be made lighter than the coaxial cable. In addition, a structure is also used in which an NMR signal is converted from an electrical signal to an optical signal in an RF receiving coil and transmitted to a computer by an optical fiber cable.

  Furthermore, in Patent Document 1 and Patent Document 2, it is proposed to wirelessly transmit the NMR signal from the inside of the RF receiving coil to the computer. By making it wireless, it is possible to eliminate the cable for signal transmission from the RF receiving coil to the computer.

  By radioizing the transmission of NMR signals from within the RF receiving coil to the computer, the cable for signal transmission from the RF receiving coil to the computer can be eliminated, but a radio communication circuit or the like disposed in the RF receiving coil It is necessary to supply power for operating the A / D converter and the like. Patent Document 1 and Patent Document 2 propose a structure in which a power coupling coil is disposed in an RF receiving coil, inductively coupled to a power coupling coil outside the RF receiving coil, and power is supplied by an induction field. . At this time, the frequency of the induction field is different from the resonance frequency of the NMR signal. Specifically, the frequency of the induction field for supplying power is set so that the frequency interval of its harmonic peak group becomes larger than the frequency bandwidth of the resonance frequency band of the RF receiving coil, and A sufficiently high frequency is selected so that no multiple of the frequency falls within the resonant frequency band of the RF receive coil.

Patent No. 5547724 gazette Patent No. 4856094

  The attachment position and shape of the RF receiving coil to the subject vary depending on the region and the position of the subject to be imaged in order to obtain high image quality. Therefore, the relative positional relationship such as the distance between the power coupling coil disposed in the RF receiving coil and the power coupling coil on the supply side provided outside the RF receiving coil, such as the angle between the two, is determined by the subject. Because the power coupling efficiency also changes according to the imaging site and posture of the subject, stable power supply is difficult.

  An object of the present invention is to stably feed power to an RF receiving coil regardless of an imaging region and a body position of an examination object.

  In order to solve the above problems, according to the present invention, there is provided a table for mounting an inspection object, a fixture for fixing the inspection object to the table, and a receiving coil unit for receiving a nuclear magnetic resonance signal from the inspection object. There is provided an MRI apparatus comprising: a calculation unit that receives a nuclear magnetic resonance signal received by a receiving coil unit and reconstructs an image of an examination object. The fixture includes a power feeding unit for supplying power to the receiving coil unit, and the receiving coil unit includes a power receiving unit that receives power from the power feeding unit.

  According to the present invention, power can be stably supplied to an RF receiving coil that transmits an NMR signal wirelessly, regardless of the imaging region and body position of the examination target.

FIG. 1 is a block diagram showing the configuration of an MRI apparatus according to a first embodiment. (A) is sectional drawing of RF receiving coil unit of 1st embodiment, and fixing tool, (b) is an enlarged view of the receiving part 415 of a figure (a). (A) is a top view of RF receiving coil unit of 1st embodiment, (b) is a figure which shows the receiving coil element 302 and receiver 303 inside RF receiving coil unit. The block diagram of the power transmission part in the fixing tool of 1st embodiment of this invention. The block diagram of the call | power receiving part in RF receiving coil unit of 1st embodiment of this invention. (A-1) top view and (a-2) side view of the wiring and the substrate on which the wiring is mounted in the fixture of the first embodiment, (b-1) top view at the time of extension, (b-2) The side view at the time of extension. (A) Top view of the fixing tool and top plate of 1st embodiment, (b) Sectional drawing. The figure which shows the timing of on-off of the imaging sequence of 1st embodiment, and a control signal. (A) is a cross-sectional view of the RF receiving coil unit and the fixture of the second embodiment, (b) is a cross-sectional structure of the power transmission unit of the fixture and the power receiving unit of the RF receiving coil unit Figure showing. The block diagram of the power transmission part in the fixing tool of 2nd embodiment, and the call | power receiving part in RF receiving coil unit.

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

<< First Embodiment >>
An MRI apparatus according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 5.

<Overall structure of MRI apparatus>
As shown in FIG. 1, in the MRI apparatus of this embodiment, a magnet 101 for generating a static magnetic field, a gradient magnetic field generating coil 102 for generating a gradient magnetic field, and an RF irradiation coil 103 for generating a high frequency magnetic field are disposed inside. A gantry 100 is provided.

  At the opening provided in the gantry 100, a table 400 on which the inspection object 104 is mounted is disposed. The table 400 is provided with a fixture 403 for fixing the inspection object 104 to the table.

  Further, in the inspection target 104, an RF receiving coil unit 300 for receiving an NMR signal generated by the inspection target 104 is mounted on the imaging target portion. As shown in FIGS. 1 and 2A, the RF receiving coil unit 300 includes a receiving coil element 302 for receiving an NMR signal from the inspection object 104, and a wireless communication unit 501-1 for wirelessly transmitting the received NMR signal. Is equipped.

  The top board stationary RF receiving coil unit 301 may be fixed on the top board 402 of the table 400. The top board stationary RF receiving coil unit 301 also includes a wireless communication unit 501-2 that wirelessly transmits the received NMR signal.

  The table 400 incorporates a drive unit for moving the top plate 402, and the table control unit 202 is connected to the drive unit. The table control unit 202 moves the top 402 of the table 400 and arranges the imaging region of the inspection object 104 in the imaging space in the opening of the gantry 100.

  The gradient magnetic field generating coil 102 is configured of gradient magnetic field coils that respectively generate gradient magnetic fields in three axial directions orthogonal to each other. Each of the gradient magnetic field coils is connected to the gradient magnetic field power supply 108 and receives supply of pulse signals for generating a magnetic field gradient from the magnetic field gradient power supply 108. Thereby, each of the gradient magnetic field coils generates gradient magnetic fields in three axial directions in the imaging space.

  A high frequency magnetic field generator 107 is connected to the RF irradiation coil 103, and by receiving supply of an RF signal from the high frequency magnetic field generator 107, the test object 104 in the imaging space is irradiated with an RF magnetic field pulse.

  The RF receiving coil unit 300, 301 includes a receiving coil element 302 and a receiver 303, and digitizes after receiving an NMR signal generated by the inspection object 104 irradiated with an RF magnetic field pulse. The wireless communication units 501-1 and 501-2 modulate the digitized NMR signals into radio waves conforming to the wireless standard, and transmit the signals to the wireless control unit 502 by wireless communication. (Although not shown, the receiving coil element 302 and the receiver 303 are provided in the RF receiving coil unit 301 as well as 300.)

  The sequencer 200 is connected to the table control unit 202, the high frequency magnetic field generator 107, and the gradient magnetic field power supply 108, and outputs an instruction for instructing operation timing. A calculation unit 601 is connected to the sequencer 200 and the wireless control unit 502.

  The calculation unit 601 controls the sequencer 200 to apply a gradient magnetic field pulse and irradiate an RF magnetic field pulse at a predetermined timing and intensity, and at the same time, receive an NMR signal at a predetermined timing. The imaging pulse sequence is executed.

  Also, the calculation unit 601 performs image reconstruction using the NMR signal received by the wireless control unit 502. The reconstructed images are stored in the storage medium 602 connected to the calculation unit 601, and displayed on the display device 603.

<Feeding structure for RF receiving coil unit 300>
As shown in FIG. 2A, in the present embodiment, the fixture 403 is provided with a power feeding unit 415 for supplying power to the RF receiving coil unit 300. The receiving coil unit 300 is provided with a power receiving unit 408 that receives power from the power feeding unit 415.

  The fixing tool 403 is wound around the inspection object 104 from above the RF reception coil unit 300 at a position where the RF reception coil unit 300 of the inspection object 104 is placed, and the inspection object 104 is fixed to the top plate 402 The receiving coil unit 300 is fixed to the inspection object 104.

  As described above, in the present embodiment, when the fixing object 403 for fixing the inspection object 104 to the top plate 402 is provided with the power feeding unit 415, when the inspection object 104 is fixed by the fixing member 403, the power feeding unit 415 and RF Since the positional relationship with the power receiving unit 408 of the receiving coil unit 300 is maintained, power can be stably supplied to the power receiving unit 408 of the RF receiving coil unit 300 from the power feeding unit 415 of the fixture 403. Therefore, power can be supplied without connecting a cable for power supply to the RF receiving coil unit 300.

  The fixture 403 includes a belt portion 403-1 wound around the inspection target 104. In the example of FIG. 2A, the belt portion 403-1 is a pair, and a fastening portion 403-2 for fastening the pair of belt portions 403-1 is provided at the end of one belt portion 403-1. There is. The power feeding unit 415 includes a wire 406 disposed inside the belt unit 403-1, a fitting unit 412 disposed on a part of the belt unit 403-1, and fitted with a part of the receiving coil unit, and a power transmission unit And 407. The power transmission unit 407 receives power via the wiring 406 and supplies power to the power reception unit 408 of the reception coil unit 300. In the example of FIG. 2A, the fitting portion 412 and the power transmission portion 407 are provided at the tip of one of the belt portions 403-1. The wire 406 is provided in the belt portion 403-1 on which the power transmission unit 407 is provided.

  As an example of the fitting portion 412, as shown in FIG. 2B, a concavo-convex structure provided on a part of the housing of the power transmission part 407 and a part of the housing of the RF receiving coil unit 300 can be used. Furthermore, as shown in FIG. 2B, the surface fastener 420 may be disposed at a portion where the housing of the power transmission unit 407 and the housing of the RF receiving coil unit 300 face each other. Thus, both positioned by the fitting portion 412 can be fixed by the surface fastener 420.

  FIG. 3A shows a top view of the RF receiving coil unit 300. As shown in FIG. As shown in FIG. 3A, the fitting portion 412 and the surface fastener 420 may be provided at a plurality of places. When these are provided at a plurality of locations, the fitting portion 412 of the power feeding portion 415 and the surface fastener 420 can be attached to the fitting portion 412 and the surface fastener 420 at any one position depending on the size of the inspection object 104 and the imaging region. Can be fitted and fixed. Further, FIG. 3B shows a schematic view of the inside of the RF receiving coil unit 300. As shown in FIG. Thus, the receiving coil element 302 and the receiver 303 are incorporated in the RF receiving coil unit 300.

  The wiring 406 of the belt portion 403-1 is electrically connected to the power supply cable 401 disposed in the top plate 402. As shown in FIG. 1, the receiving coil power supply 201 is connected to the cable 401, and power to be supplied to the receiving coil unit 300 is supplied.

  Further, in the case where the top-plate stationary RF reception coil unit 301 is fixed on the top plate 402 of the table 400, the top-plate stationary RF reception coil unit 301 is also provided on the top plate 402. It is connected to the cable 401 in the top 402 via 404 and receives power from the cable 401.

  The structures of the power transmission unit 407 and the power reception unit 408 will be further described with reference to FIGS. 4 and 5.

  The power transmission unit 407 of the fixture 403 includes a power transmission coil 802 as shown in FIG. 4, and the power reception unit 408 of the RF receiving coil unit 300 includes a power reception coil 809 as shown in FIG. 5.

  The fixing tool 403 holds the power transmission coil 802 in a predetermined positional relationship with the power reception coil 809 by fitting the fitting portion 412 to a part of the RF reception coil unit 300. That is, as shown in FIG. 2B, the distance D between the power transmission coil 802 of the power transmission unit 407 and the power reception coil 802 of the power reception unit 408 becomes constant due to the fitting of the fitting portion 412. Furthermore, by the surface fasteners 420 being joined to each other, both are fixed and the distance D can be stably maintained.

  The details of the power transmission unit 407 and the power reception unit 408 will be further described.

  The power transmission unit 407 includes a high frequency generation circuit 801 and a signal processing circuit 803 in addition to the power transmission coil 802 as the circuit configuration is shown in FIG. 4. The signal processing circuit 803 includes a multiplier 805, a filter 806, an amplifier 807, a feedback circuit 808, a regulator 804, a comparator 814, and a ROM 815. The power supplied at various levels from wiring 406 is multiplied by a high frequency signal output from high frequency generation circuit 801 by multiplier 805 to be converted to a high frequency, and then appropriately processed by signal processing circuit 803. Then, it is supplied to the coil 802 and irradiated as an electromagnetic field from the coil 802.

  Here, the high frequency generation circuit 801 and the signal processing circuit 803 are in the band of the resonance frequency of the NMR signal so that the electromagnetic field irradiated from the power transmission coil 802 has a frequency different from the resonance frequency of the NMR signal of the inspection object 104. After sufficiently attenuating a certain signal component, the signal processing is performed so as to be amplified to a minimum appropriate level necessary for power transmission. Therefore, the power transmission unit 407 is also supplied with a signal "Charge" for controlling the high frequency generation circuit 801 and the signal processing circuit 803 separately from the line supplying the power "Power".

  Further, the ROM 815 of the power transmission unit 407 stores in advance information on the amount of power required by the load (receiving coil unit 300) side. The comparator 814 compares the power detected by the feedback circuit 808 with the power amount information stored in the ROM 814, and if the detected power is larger than the power amount required by the receiving coil unit 300, It also has a function of lighting the connected LED 816. The LED 816 is disposed outside the housing of the power transmission unit 407, and when the LED 816 lights up, it notifies the user that the power supply is sufficient.

  On the other hand, as shown in the circuit configuration in FIG. 5, the power receiving unit 408 includes, in addition to the power receiving coil 809, a matching circuit 810, an RF-DC converter 811, and a power control circuit 812. The power receiving coil 809 receives wireless power transmission from the above-described power transmitting coil 802 by electromagnetic field coupling or the like using near-field inductive coupling. The electromagnetic field fluctuation component (RF component) generated by the power transmission coil 802 is detected by the power reception coil 809 and converted to direct current by the RF-DC converter 811. At this time, the matching circuit 810 is adjusted so that the electromagnetic field fluctuation component is not reflected, and the RF-DC converter 811 can convert the RF component into a DC component, that is, a DC power supply with low noise.

  The RF receiving coil unit 300 includes a receiver 303, a battery 813-1 and a wireless communication unit 501-1 as a load circuit 813 requiring electric power. The receiver 303 includes a decoupler 303-1 and a preamplifier (including an A / D converter) 303-2. The NMR signal generated by the inspection object 104 is received by the reception coil element 302, subjected to analog processing such as amplification and filtering by the preamplifier 303-2 of the receiver 303, and is A / D converted. The digitized NMR signal is modulated to a radio wave that meets the wireless standard required by the wireless communication unit 501-1 and wirelessly transmitted to the wireless control unit 502.

  The components converted into DC power by the RF-DC converter 811 are appropriately distributed by the power control circuit 812 to each part of the load circuit 813 in the RF receiving coil unit 300. The control signal for controlling the distribution operation of the power supply control unit 812 (for example, a decoupler circuit ON trigger signal “Decoupler” or a battery operation start control signal “Battery_ON” shown in FIG. 8 described later) It is calculated from the control signal “Tx” for transmitting the high frequency magnetic field pulse and the control signal “Rx” indicating the reception timing of the reception signal in the RF receiving coil unit 300, and the power is supplied from the wireless control unit 502 via the wireless communication unit 501-1. It is transmitted to the control unit 812.

  Next, the wiring 406 disposed in the belt portion 403-1 of the fixture 403 will be described with reference to FIG.

  The belt portion 403-1 and the wire 406 have a flexible structure that is stretchable in the present embodiment. By using the flexible belt portion 403-1 and the wire 406, even if the size of the inspection object 104 is different, the inspection object 104 is fixed to the top plate 402 by fastening the belt portion 403-1. And the RF receiving coil unit 300 can be fixed to the inspection object 104. Also, power can be supplied to the RF receiving coil unit 300 through the wiring 406 that expands and contracts.

  For example, as shown in FIGS. 6 (a-1) and 6 (a-2) respectively, as the top view and the side view, the wiring 406 is mounted, for example, inside the belt portion 403-1 made of a stretchable material. A flexible substrate 406-1 is provided. The substrate 406-1 is obtained by forming a stretchable base material (for example, a polyimide base material) into a strip shape, and is mounted with the wiring 406 meandered in a meander shape. The wirings 406 are fixed to the substrate 406-1 by jigs 406-2 arranged at predetermined intervals. As a result, since the meandering shape of the wiring 406 can be deformed in the portion where the jig 406-2 is not disposed, as shown in FIGS. 6 (b-1) and (b-2), the base member 406-1 The wire 406 is also extended by extending the

  Further, as shown in FIG. 6A, one or more wires 1406 and the like which are meandered are wired in addition to the wire 406 which is meandered. As a result, the wire 406 for supplying power to the power transmission unit 407 and the wire 1406 for supplying the control signal "Charge" can be made parallel to each other and can be wired to the belt portion 403-1 so that the power and the control signal are simultaneously transmitted. It is possible to do.

  Further, as shown in FIG. 6, the stretchable flexible substrate 406-1 is divided into a plurality of portions, the non-stretchable substrate 409 is connected and integrated between them, and it is molded with a flexible material such as polyethylene resin. A telescopic fastener 403 can also be realized. The fastening portion 403-2, the transmission portion 407, and the fitting portion 412 are mounted on the substrate 409 which does not expand and contract.

  Next, the power transmission structure from the cable 401 in the top plate 402 to the fixture 403 will be described using FIGS. 7A and 7B.

  As described above, the belt portion 403-1 of the fixture 403 includes the telescopic wire 406 inside. One end of the wiring is connected to the power transmission unit 407, and the other end is connected to the cable 401 in the top plate 402. A top plate groove 416 is formed on the top surface of the top plate 402 at an edge along the long axis direction (Z direction). At an end portion of the fixture 403, an engagement portion 410 provided with a convex portion that engages with the top plate groove 416 is provided. Thereby, the fixing tool 403 is movable in the Z direction along the top plate groove 416 in a state in which the engaging portion 410 is engaged with the top plate groove 416.

  Further, the cable 401 in the top plate 402 is drawn out from the top plate 402 and connected to the wire 406 of the belt portion 403-1 of the fixture 403. At this time, the length of the cable 401 pulled out from the top plate 402 is longer than the length of the top plate groove 416 of the top plate 402, and is wound by the cable winding mechanism 411 disposed on the lower surface of the top plate 402. ing. As a result, even when the fixture 403 is moved to any position along the top plate groove 416, the cable 401 is pulled out from the cable winding mechanism 411, so the connection state between the cable 401 and the wiring 406 of the fixture 403 You can keep That is, regardless of the position of flexible RF receiving coil unit 300 provided with wireless communication unit 501-1 on top plate 402, fixing tool 403 is moved to that position, and fixing tool 403 enables RF receiving coil unit 300. Can be fixed to the inspection object 104, and power can be supplied to the RF receiving coil unit 300.

  Next, an imaging sequence and power feeding control of the RF receiving coil unit 300 will be described with reference to FIG.

  FIG. 8 shows an imaging sequence, and a control signal “Tx” for transmitting an RF magnetic field pulse from the RF irradiation coil 103 and a control signal “Rx” signal showing acquisition timing of a reception signal in the RF reception coil unit 300 are desired imagings. It is predetermined by the parameters of the sequence (TR / TE etc.). Therefore, the RF magnetic field pulse is irradiated from the RF irradiation coil 103 when the “Tx” signal is turned on, and the “decoupler” signal is turned on almost simultaneously (in fact, several microseconds before). The decoupler 303-1 of the switch 303 is turned on to prevent the RF receiving coil unit 300 from receiving RF magnetic field pulses. The "decoupler" signal is turned off almost simultaneously with the "tx" signal off (in fact, after several microseconds). The “decoupler” signal is transmitted to the RF receiving coil unit 300 via the wireless communication unit 501.

  Further, the “charge” signal is supplied to the power transmission unit 407 through the wiring 1406 of the fixture 403. The “charge” signal is a signal that controls the signal processing circuit 803 of the power transmission unit as described above. Basically, the signal processing circuit 803 is operated, and power is supplied from the power transmission unit 407 to the power reception unit 408.

  However, while the “Rx” signal is ON, the RF reception coil unit 300 receives the NMR signal, and transmits the received NMR signal from the wireless communication unit 501-1 to the wireless control unit 502 during the “Charge” signal. Is turned off. The operations of the high frequency oscillator 801 and the signal processing circuit 803 of the power transmission unit 407 are stopped, and the power supply to the power reception unit is stopped. As a result, while the RF receiving coil unit 300 wirelessly transmits the NMR signal, power feeding from the power transmission unit 407 of the fixture 403 to the receiving coil unit 300 is stopped, so the NMR signal transmitted wirelessly is The electromagnetic waves transmitted from the power transmission coil 802 can be prevented from being mixed as noise. The "charge" signal is controlled to be turned off only while the "Rx" signal is on, and to be turned on again as soon as the "Rx" signal is turned off.

  However, the decoupler 303-1 in the RF receiving coil unit 300 and the preamplifier (including an A / D converter) 303-2 operate while the wireless transmission of the NMR signal is stopped while the power feeding from the power transmitting unit 407 is stopped. You need to Therefore, the operation of the power control unit 812 is controlled to turn on the power supply to the battery 813-1 before the “Rx” signal is turned on (eg, at the timing when the “Tx” signal is turned off). The control signal “Battery_ON” signal is passed from the wireless control unit 502 to the power control unit 812 via the wireless reception unit 501-1.

  Thus, since battery 813-1 is charged, decoupler 303-1 in the RF receiving coil unit 300 and the preamplifier (including the A / D converter are included even while power supply from power transmission unit 407 is stopped. ) 303-2 can be powered from the battery.

  As described above, by controlling the power transmission unit 407 and the power reception unit 408 according to the imaging sequence, the RF receiving coil unit 300 from the fixture 403 by wireless power transmission such as near-field inductive coupling (electromagnetic coupling using the near-field). Power is supplied, and while the “Rx” signal is ON, that is, while the receiving coil receives an NMR signal and transmits wirelessly, the power supply by wireless power transmission is stopped, and the electromagnetic noise is an NMR signal. Can be prevented from mixing into

  As described above, in the present embodiment, it is not necessary to connect a cable for feeding power to the RF receiving coil unit 300 provided with the wireless communication unit 501-1, and moreover, from the wiring 406 disposed in the fixture 403 Power can be stably supplied to the reception cor unit 300.

  Further, in addition to the wire 406 for feeding power to the belt portion 403-1 of the fixture 403, it is possible to arrange a wire 1406 for a control signal line. It is also possible to transmit the control signal via the belt unit 403-1.

  In the first embodiment, the RF receiving coil unit 300 includes the wireless communication unit 501-1 and wirelessly transmits the received NMR signal. However, the present invention is not limited to this configuration. Alternatively, the NMR signal received by the RF receiving coil unit 300 may be delivered to the fixture 403, and may be delivered to the calculation unit 601 via the wiring in the fixture 403. In this case, the fixture 403 is provided with a wire for transmitting an NMR signal in addition to the wire 406 for feeding and the wire 1406 for control signal. In addition, the fixture 403 is provided with an output unit for outputting an NMR signal, and an input unit for receiving the NMR signal from the output unit is provided in the fixture 403. Each of the output unit and the input unit has a coil disposed to face each other as in the case of the power supply unit 407 and the power reception unit 408 described above, and an NMR signal by non-contact transmission such as electromagnetic coupling using near field. The transfer of NMR signals may be performed by bringing the terminals into contact with each other. As described above, the RF signal receiving coil unit 300 having no wireless communication function can be fixed by passing the NMR signal from the RF receiving coil unit 300 to the calculating unit 601 through the fixing member 403. There is no need to connect any other wiring, and a user-friendly RF receiving coil unit 300 can be provided.

<< Second Embodiment >>
Next, an MRI apparatus according to a second embodiment of the present invention will be described with reference to FIGS. 1, 9 and 10.

  The MRI apparatus of the second embodiment is different from the first embodiment in that the power transmission unit 407 and the power reception unit 408 are in direct contact with each other by the power transmission terminal 413 and the power reception terminal 414, and transmit power. Hereinafter, only the configuration different from the first embodiment will be described, and the description of the same configuration will be omitted.

  As shown in FIGS. 9 and 10, the power transmission unit 407 of the fixture 403 includes a power transmission terminal 413, and the power reception unit 408 of the RF reception coil unit 300 includes a power reception terminal 414. In the present embodiment, the power transmission terminal 413 includes two terminals 413a and 413b, the power reception terminal 414 includes two terminals 414a and 414b, and both the power and the control signal can be transmitted from the fixture 403 to the RF receiving coil unit 300. Transmit to Here, conductive surface fasteners are used as the power transmission terminals 413a and 413b and the power reception terminals 414a and 414b. By reversing the unevenness of the conductive surface fastener between the power transmission terminals 413a and 413b, it is possible to prevent erroneous connection in which the power reception terminals 414a and 414b are connected in a mixed manner.

  In the present embodiment, in order to prevent an electric shock when the inspection object 104 or the like comes in contact with the power transmission terminal 413 and the power reception terminal 414, the power supplied to the power transmission terminal 413a for transmitting power is set to a low voltage.

  As shown in FIG. 10, power reception unit 408 includes amplifier 1807, charge pump 1808, low pass filter 1809, and power supply control unit 812, and amplifies low voltage power received from power transmission unit 407 by amplifier 1807 and charge pump 1808. After the high frequency component is removed by the low pass filter 1809, the power supply control unit 812 supplies power to the receiver 303, the battery 813-1 and the wireless communication unit 501-1.

  Further, the power receiving terminal 414 b that receives the control signal from the power transmission terminal 413 b passes the control signal to the power control 812, and is used for control of the power control 812.

  As described above, in the MRI apparatus of the second embodiment, power and control signals can be supplied from the fixture 403 to the RF receiving coil unit 300 using the structure in which the terminals are in contact.

  Note that the control signal may not necessarily be supplied from the fixture 403 to the RF receiving coil unit 300, and as in the first embodiment, wireless communication from the wireless control unit 502 via the wireless communication unit 501-1. You may receive it at

100 gantry 101 magnet 102 gradient magnetic field generating coil 103 RF irradiation coil 104 inspection object 107 radio frequency (RF) magnetic field generator 108 gradient magnetic field power supply 200 sequencer 201 coil control unit (including reception coil power supply unit)
202 Table control unit 300 RF receiving coil unit 301 top plate stationary RF receiving coil unit 302 receiving coil element 303 receiver 400 table 401 cable 402 top plate 403 fixture 403-1 belt portion 403-2 fastening portion 404 top plate connector 406 wiring 406-1 flexible substrate 406-2 fixing jig 407 power transmission unit 408 power reception unit 409 substrate 410 engagement unit 411 cable winding mechanism 412 fitting unit 413 power transmission terminal 414 power reception terminal 415 feeding unit 416 top plate groove 420 surface fastener 501- 1,501-2 Radio Communication Unit 502 Radio Control Unit 601 Calculation Unit (Image Reconstruction Unit)
602 storage medium 603 display device 801 high frequency generation circuit 802 power transmission coil 803 signal processing circuit 804 regulator 805 multiplier (mixer)
806 filter 807 amplifier 808 feedback circuit (TANK circuit, detection circuit)
809 power reception circuit 810 matching circuit 811 RF-DC conversion circuit 812 power supply control circuit 813 load circuit 814 comparator 815 ROM
816 LED
1406 Second Wiring 1807 Amplifier 1808 Charge Pump Circuit 1809 Low Pass Filter

Claims (14)

A table for mounting an inspection object, a fixture for fixing the inspection object on the table, a receiving coil unit for receiving a nuclear magnetic resonance signal from the inspection object, and a nuclear magnetic resonance signal received by the receiving coil unit And a calculation unit for receiving the image to reconstruct the image of the inspection object,
The fixture includes a power feeding unit for supplying power to the receiving coil unit, and the receiving coil unit includes a power receiving unit for receiving power from the power feeding unit. Resonance imaging device. The magnetic resonance imaging apparatus according to claim 1, wherein the receiving coil unit includes a wireless communication unit that wirelessly transmits the received nuclear magnetic resonance signal to the calculation unit.
The magnetic resonance imaging apparatus, wherein the power supply unit supplies power to at least the wireless communication unit.   The magnetic resonance imaging apparatus according to claim 1, wherein the reception coil unit is placed on the inspection target, and the fixing tool is wound around the inspection target from above the reception coil unit. A magnetic resonance imaging apparatus characterized in that the inspection object is fixed to the table, and the receiving coil unit is fixed to the inspection object. The magnetic resonance imaging apparatus according to claim 1, wherein the fixing device includes a belt portion wound around the inspection object.
The power feeding unit includes a wire disposed inside the belt unit, and a fitting unit and a power transmission unit disposed in a part of the belt unit and fitted with a part of the receiving coil unit, A magnetic resonance imaging apparatus, wherein the unit receives power via the wiring and feeds power to a power receiving unit of the receiving coil unit. The magnetic resonance imaging apparatus according to claim 4, wherein the power transmission unit includes a power transmission coil.
The power receiving unit of the receiving coil unit includes a power receiving coil,
The magnetic resonance imaging apparatus characterized in that the power feeding unit holds the power transmission coil in a predetermined positional relationship with respect to the power receiving coil by fitting the power feeding unit to a part of the receiving coil unit by the fitting unit. . 5. The magnetic resonance imaging apparatus according to claim 4, wherein the power feeding unit includes a power transmission terminal, the belt unit is provided with a wire for feeding power to the power transmission terminal, and the power receiving unit of the receiving coil unit is , Receiving terminal,
The magnetic resonance imaging apparatus characterized in that the power feeding unit electrically feeds the power transmission terminal to the power reception terminal by fitting the power transmission unit to a part of the reception coil unit by the fitting unit. .   5. The magnetic resonance imaging apparatus according to claim 4, wherein the belt portion and the wire have stretchable flexibility. The magnetic resonance imaging apparatus according to claim 2, further comprising: a control unit configured to control power supply timing from the power supply unit of the fixture to the reception coil unit, and timing of the wireless transmission by the reception coil unit. Have
The magnetic resonance imaging according to claim 1, wherein the control unit stops the power supply from the power supply unit of the fixture to the reception coil unit while the reception coil unit wirelessly transmits the nuclear magnetic resonance signal. apparatus.   The magnetic resonance imaging apparatus according to claim 8, wherein the receiving coil unit includes a battery for storing a part of the power received by the power receiving unit, and the power feeding unit supplies power from the power feeding unit to the power receiving unit. A magnetic resonance imaging apparatus characterized in that power is supplied from the battery to the wireless communication unit when the power supply is stopped.   5. The magnetic resonance imaging apparatus according to claim 4, wherein a control signal wire for transmitting a control signal to a circuit in the power transmission unit is further disposed in the belt unit. Resonance imaging device.   The magnetic resonance imaging apparatus according to claim 5, wherein the power transmission coil supplies power to the power receiving coil by wireless power transmission.   The magnetic resonance imaging apparatus according to claim 1, wherein the power feeding unit includes an LED that lights up when an amount of power supplied to the power receiving unit is equal to or more than a predetermined amount.   A fixture for fixing an examination object to a table of a magnetic resonance imaging apparatus, comprising: a power feeding unit for supplying power to a receiving coil unit that receives a nuclear magnetic resonance signal from the examination object. Fasteners for magnetic resonance imaging equipment.   The fixture for a magnetic resonance imaging apparatus according to claim 13, wherein the reception coil unit includes a circuit for wirelessly transmitting a reception signal having received the nuclear magnetic resonance signal, and the power supply unit transmits at least the wireless transmission. A fixture for a magnetic resonance imaging apparatus characterized by supplying power to a circuit.

Images