JP6203002B2 - Magnetic resonance imaging apparatus and RF removal filter panel unit wiring method - Google Patents

Description

  Embodiments described herein relate generally to a magnetic resonance imaging apparatus and an RF removal filter panel unit wiring method.

  MRI is an imaging method in which a nuclear spin of a subject placed in a static magnetic field is magnetically excited with an RF pulse having a Larmor frequency, and an image is reconstructed from MR signals generated by the excitation. The MRI means magnetic resonance imaging, the RF pulse means radio frequency pulse, and the MR signal means nuclear magnetic resonance signal. .

  Since the MRI apparatus detects a weak MR signal, imaging in an environment in which no radio frequency noise exists is desired. As an example of the layout of the MRI apparatus approaching such an environment, the gantry and the bed apparatus are arranged in an imaging room configured as an RF shielding room (shield room), and an operation system such as an input device is arranged in the operation room. A control system such as a gradient magnetic field power source is disposed in the computer room.

  A plurality of signal lines and power lines that pass outside and inside the imaging room are connected to respective terminals of an RF removal filter panel unit (Radio Frequency Eliminating Filter Panel Unit) installed on the wall between the imaging room and the computer room. The Since the RF noise (high frequency noise) is removed by, for example, a low-pass filter in the RF removal filter panel, it does not enter the imaging room side (see, for example, Patent Document 1).

JP 2011-72390 A

  In the computer room, there is a water cooling device for cooling the gradient magnetic field coil, and therefore, the temperature is constantly controlled so as not to cause condensation in the device. In general, since there is no entry or exit in the computer room, the setting of the air conditioner (hereinafter referred to as “air conditioner”) in the computer room is not often changed.

  On the other hand, the image pickup room is normally in a state where the air conditioner is always operated without changing the setting of the air conditioner. However, the air conditioner in the imaging room may be turned off due to misunderstanding of the operator, power saving awareness, erroneous operation, power failure, and the like. Therefore, although the temperature of the imaging room is controlled during imaging, temperature fluctuations may occur due to the above-described reason and the entry and exit of people. Furthermore, one of the air conditioner in the computer room and the air conditioner in the imaging room may break down.

  When a predetermined temperature difference occurs between the imaging room and the computer room for the above reason, if the humidity on the high temperature side is high, condensation occurs on the RF removal filter panel on the high temperature side of the imaging room and the computer room. Since the RF removal filter panel unit partitions two rooms having a temperature difference with one metal plate, condensation is likely to occur. A signal line and a power line are connected to each terminal of the RF removal filter panel unit. However, when water droplets hang down on the terminals due to condensation, troubles such as generation of a leakage current between the terminals and a short circuit between the terminals may occur.

  For this reason, in MRI, there has been a demand for a new technique for avoiding problems caused by condensation of an RF removal filter panel installed between the imaging room and the computer room.

Hereinafter, several examples of the modes that the embodiment of the present invention can take will be described for each mode.
(1) In one embodiment, the MRI apparatus includes an RF removal filter panel unit, a gantry, and a control device.
The gantry is installed in the imaging room, and the control device is installed in the computer room.
The RF removal filter panel unit is installed on the wall between the computer room and the imaging room, and has a plurality of terminals on the imaging room side and the computer room side, respectively.
The gantry includes a static magnetic field magnet, an RF coil unit that transmits an RF pulse, a gradient magnetic field coil unit that applies a gradient magnetic field, and a plurality of imaging devices respectively connected to a plurality of terminals on the imaging chamber side in the RF removal filter panel unit. And a room-side control signal line.
The control device includes a plurality of computer room side control signal lines respectively connected to a plurality of terminals on the computer room side in the RF removal filter panel unit, and includes a plurality of computer room side control signal lines and a plurality of imaging room side control signal lines. The magnetic resonance imaging is executed by transmitting a control signal to the gantry via.
The plurality of terminals on the computer room side in the RF removal filter panel unit are such that a terminal to which the first level computer room side control signal line is connected and a terminal to which the second level computer room side control signal line is connected to each other. It is wired not to be adjacent.
The plurality of terminals on the imaging room side in the RF removal filter panel unit include a terminal to which the first level imaging room side control signal line is connected and a terminal to which the second level imaging room side control signal line is connected. They are wired so that they are not adjacent to each other.

(2) In another embodiment, the RF removal filter panel unit is installed on the wall between the imaging room in which the gantry of the MRI apparatus is installed and the computer room in which the control apparatus of the MRI apparatus is installed. An interior of the imaging room side terminal group exposed to the imaging room side, a computer room side terminal group exposed to the computer room side, and each terminal of the imaging room side terminal group individually connected to each terminal of the computer room side terminal group Circuit.
And the wiring method of RF removal filter panel unit has the following steps.
One is that the control signal lines from the gantry are connected to the imaging room side terminal group so that the terminal to which the first level control signal line is connected and the terminal to which the second level control signal line is connected are not adjacent to each other. This is a step of connecting to each of the terminals.
One is that each control signal line from the control device is connected to the computer room side terminal so that the terminal to which the first level control signal line is connected and the terminal to which the second level control signal line is connected are not adjacent to each other. It is a step of connecting to each terminal of the group.

The functional block diagram which shows an example of the whole structure of the MRI apparatus of each embodiment. The upper surface schematic diagram which shows an example of the layout of each part of an MRI apparatus. An example of a wet air diagram. The partial upper surface schematic diagram of both rooms including the part of RF removal filter panel unit in the case where the temperature difference of an imaging room and a computer room is small. FIG. 5 is a schematic top view similar to FIG. 4 when the temperature difference between the imaging room and the computer room is large. The upper surface schematic diagram which shows an example of schematic structure of RF removal filter panel unit. The upper surface schematic diagram which shows an example of the wiring method of RF removal filter panel unit in 1st Embodiment. The table | surface which shows the signal level of each control signal line in the wiring example of FIG. The upper surface schematic diagram which shows the conventional wiring method with respect to RF removal filter panel unit. The upper surface schematic diagram which shows schematic structure of RF removal filter panel unit of 2nd Embodiment, and an example of the wiring method of 2nd Embodiment. The upper surface schematic diagram which shows an example of schematic structure of RF removal filter panel unit of 3rd Embodiment.

  Hereinafter, an RF removal filter panel unit wiring method and an embodiment of an MRI apparatus will be described with reference to the accompanying drawings. The main feature of each embodiment is the wiring method of the RF removal filter panel unit, etc., but the apparatus configuration of the MRI apparatus common to each embodiment, the layout example of the rooms will be described with reference to FIG. 1 and FIG. Next, the principle of condensation and the like will be described with reference to FIGS. In addition, in each figure, the same code | symbol is attached | subjected to the same element and the overlapping description is abbreviate | omitted.

<Device configuration>
FIG. 1 is a functional block diagram showing an example of the overall configuration of the MRI apparatus 18 of each embodiment. Here, as an example, the constituent elements of the MRI apparatus 18 will be described by being divided into three parts: a bed apparatus 20, a gantry 30, and a control apparatus 40.

  First, the bed apparatus 20 includes a support table 21, a top plate 22, and a top plate moving mechanism 23 disposed in the support table 21. A subject P is placed on the top surface of the top plate 22. In addition, a plurality of connection ports 25 to which the RF coil device 100 attached to the subject P is connected are arranged on the top surface of the top plate 22.

  The support base 21 supports the top plate 22 so as to be movable in the horizontal direction (Z-axis direction of the apparatus coordinate system). The top plate moving mechanism 23 adjusts the vertical position of the top plate 22 by adjusting the height of the support base 21 when the top plate 22 is located outside the gantry 30. Further, the top plate moving mechanism 23 moves the top plate 22 in the horizontal direction to put the top plate 22 into the gantry 30 and takes the top plate 22 out of the gantry 30 after imaging.

  Second, the gantry 30 is configured in a cylindrical shape, for example, and is installed in the imaging room. The gantry 30 includes a static magnetic field magnet 31, a shim coil unit 32, a gradient magnetic field coil unit 33, and an RF coil unit 34.

  The static magnetic field magnet 31 is a superconducting coil, for example, and is configured in a cylindrical shape. The static magnetic field magnet 31 forms a static magnetic field in the imaging space by a current supplied from a power supply for a superconducting coil (not shown). The imaging space means, for example, a space in the gantry 30 where the subject P is placed and a static magnetic field is applied. Note that the superconducting coil power source is not essential for subsequent imaging after the static magnetic field magnet 31 forms a static magnetic field.

  The shim coil unit 32 is configured, for example, in a cylindrical shape, and is arranged inside the static magnetic field magnet 31 with the same axis as the static magnetic field magnet 31. The shim coil unit 32 forms an offset magnetic field that makes the static magnetic field uniform by a current supplied from a shim coil power supply 44 of the control device 40 described later. The shim coil unit 32 may not be an essential element depending on the performance of the static magnetic field magnet 31.

  The gradient coil unit 33 is configured in a cylindrical shape, for example, and is disposed inside the shim coil unit 32. The gradient coil unit 33 includes an X-axis gradient coil 33x, a Y-axis gradient coil 33y, and a Z-axis gradient coil 33z.

  In this specification, it is assumed that the X axis, the Y axis, and the Z axis are the apparatus coordinate system unless otherwise specified. Here, as an example, the X axis, Y axis, and Z axis of the apparatus coordinate system are defined as follows. First, the vertical direction is the Y-axis direction, and the top plate 22 is arranged so that the normal direction of the upper surface thereof is the Y-axis direction. The horizontal movement direction of the top plate 22 is taken as the Z-axis direction, and the gantry 30 is arranged so that the axial direction becomes the Z-axis direction. The X-axis direction is a direction orthogonal to the Y-axis direction and the Z-axis direction, and is the width direction of the top plate 22 in the example of FIG.

  The X-axis gradient magnetic field coil 33x forms a gradient magnetic field Gx in the X-axis direction corresponding to a current supplied from an X-axis gradient magnetic field power supply 46x described later in the imaging region. Similarly, the Y-axis gradient magnetic field coil 33y forms in the imaging region a gradient magnetic field Gy in the Y-axis direction corresponding to a current supplied from a Y-axis gradient magnetic field power supply 46y described later. Similarly, the Z-axis gradient magnetic field coil 33z forms a gradient magnetic field Gz in the Z-axis direction corresponding to a current supplied from a Z-axis gradient magnetic field power supply 46z described later in the imaging region. The slice selection direction gradient magnetic field Gss, the phase encode direction gradient magnetic field Gpe, and the readout direction (frequency encode direction) gradient magnetic field Gro can be arbitrarily determined by combining the gradient magnetic fields Gx, Gy, and Gz in the three-axis directions of the apparatus coordinate system. Can be set in the direction of. Note that the imaging region is, for example, at least a part of an MR signal collection range used for generating an image and is an image.

  The RF coil unit 34 is configured in a cylindrical shape, for example, and is disposed inside the gradient magnetic field coil unit 33. The RF coil unit 34 includes, for example, a whole-body coil that combines RF pulse transmission and MR signal reception.

  Third, the control device 40 includes a shim coil power supply 44, a magnet monitor unit 45, a gradient magnetic field power supply 46, an RF transmitter 48, an RF receiver 50, a system control unit 61, a system bus SB, an image. It has a reconstruction unit 62, an image database 63, an image processing unit 64, an input device 72, a display device 74, and a storage device 76.

  The magnet monitor unit 45 transmits the temperature, pressure, etc. of liquid helium of a cooling device (not shown) in the static magnetic field magnet 31 to the system control unit 61. Thereby, the system control unit 61 constantly monitors whether the static magnetic field magnet 31 is abnormal.

  The gradient magnetic field power source 46 includes an X-axis gradient magnetic field power source 46x, a Y-axis gradient magnetic field power source 46y, and a Z-axis gradient magnetic field power source 46z. The X-axis gradient magnetic field power supply 46x, the Y-axis gradient magnetic field power supply 46y, and the Z-axis gradient magnetic field power supply 46z are used to generate currents for forming the gradient magnetic fields Gx, Gy, and Gz as X-axis gradient magnetic field coils 33x and Y-axis gradient magnetic field coils. 33y and the Z-axis gradient magnetic field coil 33z, respectively.

  The RF transmitter 48 generates an RF current pulse having a Larmor frequency that causes nuclear magnetic resonance based on the control information input from the system control unit 61, and transmits this to the RF coil unit 34. An RF pulse corresponding to the RF current pulse is transmitted from the RF coil unit 34 to the subject P.

  The whole body coil of the RF coil unit 34 and the RF coil device 100 attached to the subject P detect and detect the MR signal generated when the nuclear spin in the subject P is excited by the RF pulse. The MR signal is input to the RF receiver 50.

  The RF receiver 50 performs predetermined signal processing on the received MR signal and then performs A / D (analog to digital) conversion to generate raw data that is complex data of the digitized MR signal. . The RF receiver 50 inputs the raw data of the MR signal to the image reconstruction unit 62.

  The system control unit 61 performs system control of the entire MRI apparatus 18 via wiring such as the system bus SB. In addition, the system control unit 61 causes the display device 74 to display imaging condition setting screen information, and sets the imaging condition based on instruction information from the input device 72. Further, the system control unit 61 stores control information necessary for driving the gradient magnetic field power supply 46, the RF transmitter 48, and the RF receiver 50. The system control unit 61 drives the gradient magnetic field power supply 46, the RF transmitter 48, and the RF receiver 50 according to a predetermined sequence to generate gradient magnetic fields Gx, Gy, Gz, and RF pulses.

The input device 72 provides a user with a function of setting imaging conditions and image processing conditions.
The image reconstruction unit 62 arranges and stores the raw data of the MR signal input from the RF receiver 50 as k-space data according to the number of phase encoding steps and the number of frequency encoding steps. The k space means a frequency space. The image reconstruction unit 62 generates image data of the subject P by performing image reconstruction processing including Fourier transform on the k-space data.

  In the above description, the components of the MRI apparatus 18 are classified into the gantry 30, the bed apparatus 20, and the control apparatus 40. However, this is only an interpretation example. For example, the top plate moving mechanism 23 may be regarded as a part of the control device 40. Alternatively, the RF receiver 50 may be disposed inside the gantry 30 instead of outside the gantry 30.

  The imaging operation of the MRI apparatus 18 is as follows, for example. The RF coil device 100 is set on the subject P on the top plate 22, and a static magnetic field is formed in the imaging space by the excited static magnetic field magnet 31. Further, current is supplied from the shim coil power supply 44 to the shim coil unit 32 as necessary, and the static magnetic field formed in the imaging space is made uniform.

  Thereafter, the system control unit 61 drives the gradient magnetic field power source 46, the RF transmitter 48, and the RF receiver 50 in accordance with the pulse sequence, thereby forming a gradient magnetic field in the imaging region including the imaging region of the subject P. Then, an RF pulse is generated from the RF coil unit 34. Note that the above-described imaging region means which part of the subject P such as the chest is imaged as an imaging region.

  Therefore, an MR signal generated by nuclear magnetic resonance in the subject P is detected by the RF coil device 100 and input to the RF receiver 50. The RF receiver 50 generates the raw data of the MR signal by performing the above-described processing on the MR signal, and inputs the raw data to the image reconstruction unit 62. The image reconstruction unit 62 arranges and stores the raw data of the MR signal as k-space data, reconstructs the image data by performing the above-described image reconstruction process, and stores the image data in the image database 63. .

  The image processing unit 64 takes in image data from the image database 63, performs predetermined image processing on the image data, generates two-dimensional display image data, and stores the display image data in the storage device 76. The system control unit 61 causes the display device 74 to display an image indicated by the display image data.

  FIG. 2 is a schematic top view showing an example of the layout of each part of the MRI apparatus 18. As illustrated in FIG. 2, as an example, the computer room 300 and the operation room 400 are partitioned by a wall so as to be adjacent to the imaging room 200 configured as a shield room. A door 202 having an RF blocking function is provided on the entrance side of the imaging room 200, and a subject (patient) can enter the imaging room from here. Between the imaging room 200 and the operation room 400, a door 204 having an RF blocking function is provided. A door 402 is provided between the computer room 300 and the operation room 400.

  A quench button CB is provided on each of the walls of the imaging room 200 and the computer room 300. The quench button CB is a forced magnetic field cutoff button for emergencies. Therefore, when the quench button CB is pressed, the system control unit 61 controls each part of the MRI apparatus 18 so as to stop the superconducting state of the static magnetic field magnet 31 that is a superconducting magnet and stop the application of the static magnetic field.

  In addition, a part of the wall between the imaging room 200 and the computer room 300 is separated from each other by an RF removal filter panel unit 500A.

  A gantry 30 and a bed apparatus 20 are arranged in the imaging room 200. However, the bed apparatus 20 may be a movable dockable type. Further, many components of the control device 40 of the MRI apparatus 18 described in FIG. 1 are arranged in the computer room 300, but the input device 72 and the display device 74 are arranged in the operation room 400.

  Although not shown in FIG. 1 because it is complicated, the control device 40 also includes a DC (Direct Current) power supply system 59. The DC power supply system 59 outputs a voltage (5 V, 10 V, etc.) suitable for the power consumption of the control circuit board in each part of the gantry 30 and operation buttons of the bed apparatus 20 and each part of the control device 40 on the computer room 300 side. Therefore, although the DC power supply system 59 includes a voltage converter, the voltage converter can be a noise source. For this reason, the DC power supply system 59 is disposed in the computer room 300 outside the imaging room 200.

  Signal lines from the quench button CB and each part of the control device 40 are connected to a computer room side terminal group 524 (see FIG. 6 described later) in the RF removal filter panel unit 500A. Signal lines from the gantry 30 and the bed apparatus 20 are connected to an imaging room side terminal group 526 (see FIG. 6 described later) in the RF removal filter panel unit 500A. Therefore, the signal lines from the quench button CB and each part of the control device 40 are connected to the gantry 30 and the couch device 20 in the imaging chamber after the high frequency noise is removed by the RF removal filter panel unit 500A.

Next, the principle of dew condensation will be described with reference to FIGS.
FIG. 3 is an example of a wet air diagram. In FIG. 3, the parameter represented by the numbers 10, 20, and 30 ° C. at the bottom of the figure is the dry bulb temperature (the temperature of a general thermometer). In FIG. 3, every time the dry bulb temperature rises by 1 ° C., it is divided by a substantially vertical straight line.

The parameter indicated by the right-downward straight lines drawn at 5 intervals from 0 to 30 is the wet bulb temperature (° C.).
The parameter shown by the upward-sloping radial curve (isohumidity curve) drawn at 10% intervals from 10% to 100% is relative humidity.

The parameter indicated by the horizontal straight lines drawn at intervals of 0.002 from 0 to 0.030 is absolute humidity.
The parameter indicated by the right-downward straight line while showing the ruler-shaped scale on the extension line is enthalpy.

  The parameter indicated by the right-downward straight lines drawn at intervals of 0.02 from 0.78 to 0.92 is the specific volume.

  The way of viewing the wet air diagram is, for example, as follows. For example, in FIG. 3, attention is paid to a plot where the dry bulb temperature is 28 ° C. and the relative humidity is 70%. The plot is moved to the left side of FIG. 3 in parallel with the horizontal straight line indicating the absolute humidity, and the dry bulb temperature corresponding to the isohumidity curve of 100% relative humidity is 21.8 ° C. Therefore, air given at a dry bulb temperature of 28 ° C. and a relative humidity of 70% becomes 100% relative humidity when condensed to 21.8 ° C., causing condensation. In the present specification, when simply expressed as “temperature”, it means “dry bulb temperature”.

  FIG. 4 is a partial schematic top view of both rooms including the RF removal filter panel unit 500A when the temperature difference between the imaging room 200 and the computer room 300 is small.

  FIG. 5 is a schematic top view similar to FIG. 4 when the temperature difference between the imaging room 200 and the computer room 300 is large.

  As shown in FIG. 4, a case is considered in which the temperatures of the computer room 300 and the imaging room 200 are, for example, 21 ° C. and 22 ° C., respectively. In this case, since the temperature difference between the two rooms is as small as 1 ° C., no condensation occurs unless the humidity of the room on the high temperature side is very high.

As shown in FIG. 5, a case is considered in which the temperatures of the computer room 300 and the imaging room 200 are, for example, 21 ° C. and 28 ° C., respectively, and the relative humidity of the imaging room 200 is 70%. In this case, since the temperature difference between the two rooms is large, condensation occurs on the high temperature room side in the RF removal filter panel unit 500A depending on the humidity of the high temperature side imaging room 200. As described above, since air having a temperature of 28 ° C. and a relative humidity of 70% is condensed when the temperature is lowered to 21.8 ° C., condensation can occur when the relative humidity of the imaging chamber 200 is 70% or more.
The above is a description of the principle of dew condensation, and its features will be described below for each embodiment.

<First Embodiment>
FIG. 6 is a schematic top view illustrating an example of a schematic configuration of the RF removal filter panel unit 500A. In FIG. 6, the right side of the drawing is the imaging room 200 side, and the left side of the drawing is the computer room 300 side. The imaging room 200 is covered with a metal shield 210 for blocking radio waves. The imaging shield side of the metal shield 210 is partitioned as a wall having a certain strength by the wall material 220 including the interior material, and the computer room 300 side of the metal shield 210 is partitioned by the wall material 320 including the interior material.

  The RF removal filter panel unit 500A includes a filter panel 504, a fixture 506, a protective cover 510 on the computer room 300 side indicated by a thick line, a protective cover 512 on the imaging room 200 side indicated by a thick line, and a plurality of (for RF removal). A filter circuit 520, a computer room side terminal group 524, and an imaging room side terminal group 526.

Since it becomes complicated, here, as an example, the computer room side terminal group 524 and the imaging room side terminal group 526 each have 10 terminals 1 to 10 and 1 ′ to 10 ′.
Terminals 1 to 10, 1 'to 10' are electrical signal line connection fasteners.

  The filter circuit 520 removes RF noise (high frequency noise) of signals input from each signal line, and has the same number as the terminals of the computer room side terminal group 524 (10 in this example). That is, the uppermost filter circuit 520 in FIG. 6 connects the terminal 1 to the terminal 1 ′ on the imaging room side while removing high-frequency noise from the signal line connected to the terminal 1 on the computer room 300 side. . Similarly, the terminals 2 to 10 of the computer room side terminal group 524 are individually connected to the terminals 2 ′ to 10 ′ of the imaging room side terminal group 526 via the filter circuit 520.

  As shown in FIG. 6 and FIG. 2 described above, between the imaging room 200 and the computer room 300, only the part of the RF removal filter panel unit 500A is opened with the metal shield 210 and the wall materials 220 and 320. In this opening portion, the filter panel 504 of the RF removal filter panel unit 500 </ b> A is fixed to the metal shield 210 by the fixture 506. The filter panel 504 is formed of a metal plate in order to block radio waves.

  In addition, when each terminal 1-10, 1'-10 'is arranged in a line along a perpendicular direction, when dew condensation arises in the uppermost terminal, a water drop will fall on a lower terminal one by one, and worst In this case, all terminals may be conductive. Therefore, it is desirable that the terminals 1 to 10, 1 'to 10' are arranged in the horizontal direction, and as an example, the terminals 1 to 10, 1 'to 10' are arranged at equal intervals in the horizontal direction.

FIG. 7 is a schematic top view illustrating an example of a wiring method of the RF removal filter panel unit 500A according to the first embodiment.
FIG. 8 is a table showing the signal level of each control signal line in the wiring example of FIG.
FIG. 9 is a schematic top view showing a conventional wiring method for the RF removal filter panel unit.

  Hereinafter, the difference in the wiring method between the first embodiment and the prior art will be described with reference to FIGS. Here, for simplification of explanation, it is assumed that there are five control signal lines A, B, C, D, and E, and each signal system A to E has two control signal lines. One of the signal systems A to E is a control signal line from one of the units of the control device 40 shown in FIG. 2 (for example, the gradient magnetic field power supply 44 or the RF transmitter 48).

Therefore, it can be said that the control device 40 performs magnetic resonance imaging as described at the end of FIG. 1 by transmitting a control signal to the gantry 30 and the couch device 20 via these control signal lines.
Further, the control signal line and the power line often constitute one system with two (one pair). In the above example, the power line is omitted for simplification of description, but actually the power line is also connected to the RF removal filter panel unit 500A (not shown).

  In FIG. 7, the control signal lines A1 and A2 of the signal system A are indicated by bold lines, the control signal lines B1 and B2 of the signal system B are indicated by solid lines, and the control signal lines C1 and C2 of the signal system C are indicated by broken lines. The control signal lines D1 and D2 of the signal system D are indicated by a one-dot chain line, and the control signal lines E1 and E2 of the signal system E are indicated by a two-dot chain line.

  In the first embodiment, the control signal lines A1, B1, and C1, which are fixed at a high level in the normal state, have terminal numbers on the computer room 300 side and the imaging room 200 side as shown in FIGS. The younger ones (terminals 1 to 3, 1 'to 3') are connected in a concentrated manner.

  The control signal line B1 is a control signal line in which forced quenching is executed when the level is low, and is connected to, for example, the quench button CB. Therefore, when the control signal line B1 becomes conductive with other signal lines due to condensation and becomes low level, the quench button CB is pressed. This state should be avoided most from the viewpoint of wiring.

  Therefore, in the first embodiment, the control signal line A1 that is fixed at the same high level as the control signal line B1 is connected to the adjacent terminals 1 and 3 (and terminals 1 ′ and 3 ′) on both sides of the control signal line B1. , C1 are connected to each other. Therefore, even if the connection terminal 2 of the control signal line B1 becomes conductive to the adjacent terminal 1 or terminal 3 due to condensation, quenching is avoided because the terminals 1 and 3 are at the same high level as the terminal 2.

  The above-mentioned “terminal adjacent to (a certain terminal)” means, for example, “a terminal closest in position (to a certain terminal)”, and means that no other terminal is interposed therebetween. The “high level” is a positive voltage having an absolute value larger than that of “low level”, for example, and a value such as 5 V or 6 V can be used. As the “low level”, for example, voltages such as 1V and 1.5V can be used, but the ground voltage (0V) may be used as a low level.

  As shown in FIGS. 7 and 8, the control signal lines A2, B2, and C2, which are fixed at a low level in the normal state, have a larger terminal number (terminal 10 on the computer room 300 side and the imaging room 200 side). , 9, 8 and terminals 10 ', 9', 8 '). Thus, the control signal line connection terminals 1 to 3 that are normally fixed at a high level and the control signal line connection terminals 8 to 10 that are normally fixed at a low level are separated from each other (other terminals between them). Are wired). This reduces the risk of error when two adjacent terminals are conducted due to condensation.

  The control signal line E2 fixed to the reference ground potential in the normal state is connected to the terminals 7 between the terminals 1 to 3 that are normally at a high level and the terminals 8 to 10 that are normally at a low level. . An analog signal control signal line E2 is connected to a terminal 6 adjacent to the terminal 7. Thus, when the connection terminals of the control signal line E1 for the ground potential and the control signal line E2 for the analog signal are adjacent to each other so that the two (terminals 6 and 7) become conductive, the system control unit 61 can detect an abnormality.

  7 and 8, one of the remaining terminals 4 and 5 is connected to a control signal line D1 that is switched to a high level or a low level as a digital communication signal, and the other is connected to the other. A control signal line D2 is wired. The control signal line D2 is switched so as to be at a level opposite to that of the control signal line D1 as a digital communication signal. That is, during the period when the control signal line D1 is at a high level, the control signal line D2 is maintained at a low level. In this way, if the connection terminals of the two control signal lines that should be opposite to each other are adjacent to each other, the system control unit 61 can easily detect an abnormality when the two control signal lines become conductive due to condensation. .

  On the other hand, in the prior art, as shown in FIG. 9, the connection terminals of the control signal lines of the same system are wired adjacent to each other. That is, the control signal lines A1 and A2 of the signal system A are respectively connected to the terminals 1 and 2 adjacent to each other, and the control signal lines B1 and B2 of the signal system B are respectively connected to the terminals 3 and 4 adjacent to each other. It was. In FIG. 9, the control signal line with the end of the code at 1 is indicated by a solid line, and the code with the end of the code at 2 is indicated by a broken line.

  In this case, the control signal lines A2 and B2, which are fixed to the low level in the normal state, are connected to the terminals 2 and 4 adjacent to the connection terminal 3 of the control signal line B1 that is forcedly quenched when the level is low. In this case, quenching occurs when the terminal 3 is short-circuited to at least one of the adjacent terminals due to condensation. As described above, in the conventional wiring method, the connection destinations of the control signal lines of the same system are adjacent to each other only considering the intelligibility of the wiring, and the risk reduction when the adjacent terminals are short-circuited is considered. Not done.

  On the other hand, in the first embodiment, regardless of whether the control signal lines are of the same system, wiring is performed so that a fatal trouble does not occur even if a short circuit occurs with an adjacent terminal. Therefore, according to the first embodiment, regardless of whether it is artificial or non-human, the risk of trouble due to accidental condensation is easily reduced without increasing the cost. That is, in MRI, troubles due to condensation of the RF removal filter panel installed between the imaging room 200 and the computer room 300 can be avoided more than in the past.

<Second Embodiment>
FIG. 10 is a top schematic view illustrating a schematic configuration of the RF removal filter panel unit 500B of the second embodiment and an example of a wiring method of the second embodiment. In the second embodiment, a plurality of control signal lines are wired in a plurality of filter panel portions.

  As illustrated in FIG. 10, the RF removal filter panel unit 500 </ b> B includes a first RF removal filter unit 540 and a second RF removal filter unit 550. That is, the RF removal filter panel unit 500B includes the terminals 6 to 10 and 6 'to the terminals 1 to 5, 1' to 5 'of the RF removal filter panel unit 500A of the first embodiment as the first RF removal filter unit 540. 10 ′ is configured separately as the second RF removal filter unit 550.

  The first RF removal filter unit 540 includes a computer room side terminal group 544 and an imaging room side terminal group 546. The computer room side terminal group 544 has terminals 1 to 5, and the imaging room side terminal group 546 has terminals 1 ′ to 5 ′. The terminals 1 to 5 are individually connected to the terminals 1 ′ to 5 ′ by five filter circuits 520 (not shown in FIG. 10) that remove RF noise.

  The second RF removal filter unit 550 includes a computer room side terminal group 554 and an imaging room side terminal group 556. The computer room side terminal group 554 has terminals 6 to 10, and the imaging room side terminal group 556 has terminals 6 ′ to 10 ′. The terminals 6 to 10 are individually connected to the terminals 6 ′ to 10 ′ by five filter circuits 520 (not shown in FIG. 10) that remove RF noise.

  Thus, as shown in FIG. 10, the wiring of the control signal lines A1 to E2 with respect to the terminals 1 to 10, 1 ′ to 10 ′, and the terminals 6 to 10 and the terminals 6 to 10 are provided. , 6′-10 ′ side is the same as the first embodiment, except that it is structurally separated. Therefore, control signal lines A1, B1, and C1 fixed at a high level are arranged on the first RF removal filter unit 540 side, and a control signal fixed at a low level on the other second RF removal filter unit 550 side. Lines A2, B2, and C2 are arranged.

  Here, it is desirable to optimize the arrangement of the control signal lines that change to the high level or the low level in the same filter unit (540 or 550) as in the first embodiment. Accordingly, in the first RF removal filter unit 540, one of the adjacent terminals 4 and 5 is connected to the control signal line D1 that is switched to a high level or a low level, and the other is opposite to the control signal line D1. A control signal line D2 to be level is wired. Thereby, the system control part 61 can detect abnormality, when both become conductive and become the same level by dew condensation.

  Thus, also in 2nd Embodiment, the effect similar to 1st Embodiment can be acquired.

<Third Embodiment>
FIG. 11 is a schematic top view illustrating an example of a schematic configuration of an RF removal filter panel unit 500C according to the third embodiment. The third embodiment is the same as the first embodiment except that a relay terminal is further used as a modification of the first embodiment.

  As shown in FIG. 11, the RF removal filter panel unit 500C includes a filter panel 504, a fixture 506, a protective cover 510 ′ on the computer room 300 side indicated by a thick line, and a protective cover 512 on the imaging room 200 side indicated by a thick line. ', A plurality of RF removal filters 520, a computer room side terminal group 524 ′, an imaging room side terminal group 526 ′, and two relay units 580.

  The computer room side terminal group 524 'has terminals 1 to 10, and the imaging room side terminal group 526' has terminals 1 'to 10'. Which control signal line is electrically connected to each of the terminals 1 to 10, 1 'to 10' is the same as in the first embodiment.

  The terminals 10 and 10 'are each covered with a waterproof cover WP, and are configured as waterproof terminals in the third embodiment.

  Each relay unit 580 includes a relay terminal 581, a support member 582, a heat insulating material 583, a fixture 584, and a relay wiring 585.

  Since the terminals 10 and 10 ′ are configured as waterproof terminals that are treated with, for example, a sealing material, the terminals 10 and 10 ′ are electrically connected to the relay terminal 581 by the relay wiring 585 extending from the waterproof cover WP. Connected. The control signal line E2 is connected to the relay terminal 581. For example, the relay terminal 581 is fixed to a support member 582 having an L-shaped cross section. Each support member 582 is fixed to the protective covers 510 ′ and 512 ′ via the heat insulating material 583 by fastening fasteners 584 such as bolts. The necessity of the relay terminal 581 is intended to facilitate signal connection and maintenance work related to the terminal that has been subjected to the sealing material processing or the like.

  Thus, also in 3rd Embodiment, the effect similar to 1st Embodiment can be acquired. Furthermore, in the third embodiment, since the terminals 10 and 10 ′ are waterproofed, even when the surroundings are condensed, no leakage current or short circuit occurs between other terminals. In the above configuration, the control signal line E2 is disposed away from the filter panel 504 through which heat from the adjacent room (the imaging room 200 or the computer room 300) is directly transmitted.

  Even in the configuration where the filter panel 504 is disposed away from the filter panel 504, heat is transferred from the adjacent room to the relay terminal 581 via the filter panel 504, the protective cover (510 ′ or 502 ′), and the support member 582, and the relay terminal 581 is condensed. There is a fear. However, since the heat insulating material 583 is inserted between the protective cover (510 'or 502'), there is an advantage that heat in the adjacent room is hardly transmitted and condensation is not easily generated.

  In order to avoid complication, FIG. 11 shows an example in which only the terminals 10 and 10 ′ are configured as waterproof terminals. However, in order to obtain the above effect, the other terminals 1 to 9 and 1 ′ to 9 ′ are also the same. It may be configured as a waterproof terminal and connected to each control signal line via the relay unit 580.

<Supplementary items of the embodiment>
[1] In the second embodiment, an example in which a plurality of control signal lines are wired separately in the first and second RF removal filter panel sections 540 and 550 has been described. The present invention is not limited to such an embodiment. The risk due to condensation may be further reduced by wiring a plurality of control signal lines in three or more RF removal filter panel sections. Also, it is possible to arrange a plurality of RF removal filter groups such as a first RF removal filter group, a second RF removal filter group, a third RF removal filter group,... is there.

  [2] In each embodiment, one RF removing filter circuit 520 is arranged for the terminal 1 and the terminal 1 ′ connected to each other, and one RF is connected to the terminal 2 and the terminal 2 ′ connected to each other. The example in which the filter circuit 520 for removal is arranged has been described. That is, the example in which one RF removing filter circuit 520 is arranged for each pair of terminals connected to each other has been described. The embodiment of the present invention is not limited to such an aspect.

  For example, one RF removal filter circuit may be provided as a whole on the imaging room 200 side, and another RF removal filter circuit may be provided on the computer room 300 side. In this case, with respect to signals transmitted from the terminals 1 to 10 on the computer room 300 side to the terminals 1 ′ to 10 ′ on the imaging room 200 side, RF noise is removed by the RF removal filter circuit on the imaging room 200 side. Similarly, with respect to signals transmitted from the terminals 1 ′ to 10 ′ on the imaging room 200 side to the terminals 1 to 10 on the computer room 300 side, RF noise is removed by an RF removal filter circuit on the computer room 300 side.

[3] A correspondence relationship between the terms of the claims and the embodiments will be described. In addition, the correspondence shown below is one interpretation shown for reference, and does not limit the present invention.
In the computer room 300, control signal lines A 1, B 1, C 1, D 1, D 2, E 1, E 2, which come out from each part of the control device 40 and are connected to the terminals 1 to 10 of the computer room side terminal group 524, respectively. C2, B2, and A2 are examples of the computer room side control signal line recited in the claims.

In the imaging chamber, control signal lines A1, B1, C1, D1, D2, E1, E2, C2, and B2 that exit from the gantry 30 and are connected to the terminals 1 ′ to 10 ′ of the imaging chamber side terminal group 526, respectively. , A2 is an example of the imaging room side control signal line recited in the claims.
One of the high level and the low level as the signal level of each control signal line A1, A2, B1, etc. is an example of the first level described in the claims, and the other is an example of the second level described in the claims. .
The filter circuit 520 is an example of an internal circuit recited in the claims.

  [4] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

18: MRI apparatus,
20: bed apparatus, 30: gantry, 31: static magnetic field magnet, 32: shim coil unit,
33: Gradient magnetic field coil unit, 34: RF coil unit, 40: Control device,
61: System control unit, 200: Imaging room, 300: Computer room, 400: Operation room,
500A to 500C: RF removal filter panel unit

Claims (5)

An RF removal filter panel unit installed on a wall between the computer room and the imaging room, and provided with a plurality of terminals on the imaging room side and the computer room side,
A plurality of imaging chamber sides respectively connected to a plurality of terminals on the imaging chamber side in the static magnetic field magnet, an RF coil unit that transmits an RF pulse, a gradient coil unit that applies a gradient magnetic field, and an RF removal filter panel unit A gantry including a control signal line and installed in the imaging room;
A plurality of computer room side control signal lines installed in the computer room and respectively connected to a plurality of terminals on the computer room side in the RF removal filter panel unit; A control device for performing magnetic resonance imaging by a signal via the plurality of imaging room side control signal lines,
The plurality of terminals on the computer room side in the RF removal filter panel unit are connected to a terminal to which the first level computer room side control signal line is connected and to a second level computer room side control signal line. Wired so that the terminals are not adjacent to each other,
The plurality of terminals on the imaging room side in the RF removal filter panel unit are connected to a terminal to which the imaging room side control signal line at the first level is connected and the imaging room side control signal line at the second level. The magnetic resonance imaging apparatus, wherein the terminals are wired so as not to be adjacent to each other. The magnetic resonance imaging apparatus according to claim 1.
A plurality of terminals to which the computer room side control signal lines at the first level are connected are adjacent to each other, and a plurality of terminals to which the computer room side control signal lines at the second level are connected are adjacent to each other. The plurality of terminals on the computer room side in the RF removal filter panel unit are wired,
The plurality of terminals to which the imaging room side control signal lines at the first level are connected are adjacent to each other, and the plurality of terminals to which the imaging room side control signal lines at the second level are connected are adjacent to each other. Thus, the plurality of terminals on the imaging chamber side in the RF removal filter panel unit are wired. A magnetic resonance imaging apparatus, wherein: The magnetic resonance imaging apparatus according to claim 2.
Among the terminals on the computer room side in the RF removal filter panel unit, there are a plurality of terminals to which the first level computer room side control signal line is connected, and the second level computer room side control signal line. At least one terminal between a plurality of connected terminals is connected to a signal line fixed to the ground level and connected to the control device,
Among the terminals on the imaging room side in the RF removal filter panel unit, a plurality of terminals to which the imaging room side control signal lines at the first level are connected, and the imaging room side control signal lines at the second level are provided. A magnetic resonance imaging apparatus, wherein a signal line fixed to the ground level and connected to the gantry is connected to at least one terminal between a plurality of connected terminals. The magnetic resonance imaging apparatus according to claim 1.
The RF removal filter panel unit includes a first RF removal filter unit provided with a plurality of terminals on the imaging room side and the computer room side, and a plurality of terminals on the imaging room side and the computer room side, respectively. A second RF removal filter unit,
The computer room side control signal line of the first level is connected to a terminal on the computer room side in the first RF removal filter unit,
The computer room side control signal line at the second level is connected to a terminal on the computer room side in the second RF removal filter unit,
The imaging room side control signal line of the first level is connected to a terminal on the imaging room side in the first RF removal filter unit,
The imaging room side control signal line of the second level is connected to the terminal on the imaging room side in the second RF removal filter unit. An imaging room side terminal that is installed on a wall between an imaging room in which a gantry of the magnetic resonance imaging apparatus is installed and a computer room in which the control unit of the magnetic resonance imaging apparatus is installed and is exposed to the imaging room side Group, a computer room side terminal group exposed to the computer room side, and an internal circuit that individually connects each terminal of the imaging room side terminal group to each terminal of the computer room side terminal group The unit wiring method,
Each control signal line from the gantry is connected to each of the imaging room side terminal group so that the terminal to which the first level control signal line is connected and the terminal to which the second level control signal line is connected are not adjacent to each other. Connecting to each terminal;
Each control signal line from the control device is connected to the computer room side terminal group so that a terminal to which the first level control signal line is connected and a terminal to which the second level control signal line is connected are not adjacent to each other. A wiring method for the RF removal filter panel unit, comprising: connecting each terminal to each terminal.