JP2009005759A - Magnetic resonance imaging system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To turn a photography region inside a gantry to an appropriate temperature by blowing air to a part to be a high temperature locally in the photography region inside the gantry. <P>SOLUTION: In the magnetic resonance imaging system provided with the gantry 31 including a magnetostatic field generation source for forming a magnetostatic space, a bed 32 with a top plate 36 for mounting and inserting an examinee 1 to the magnetstatic space and a reception means 6 mounted on the top plate 36 for receiving nuclear magnetic resonance signals from the examinee, the system is further provided with blowing ducts 591 and 592 for blowing air to the photography region inside the gantry 31, a blowing direction control means 52 for controlling the blowing direction of the blowing ducts 591 and 592, and a plurality of temperature measuring means 47 for measuring the temperature of the photography region inside the gantry 31. The blowing direction control means 52 sets the blowing direction of the blowing ducts 591 and 592 on the basis of temperature information output from the plurality of temperature measuring means 47. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a magnetic resonance imaging (hereinafter abbreviated as MRI) apparatus that displays an image of an arbitrary cross section of a subject using a nuclear magnetic resonance phenomenon (hereinafter abbreviated as NMR), and in particular, temperature control in an imaging region. Related to technology.

  When imaging with the MRI apparatus, the subject is placed on the top, a receiving coil for receiving NMR signals is attached, the subject is moved to the imaging space, and imaging is started. In general, when the gantry is of the vertical magnetic field type, the static magnetic field is in the vertical direction, so there is a lot of space around the subject and there is a lot of natural air flow. .

  When the shape of the gantry is a horizontal magnetic field tunnel type, the space into which the subject is inserted is determined by the performance of the MRI apparatus. Therefore, when the subject is large, the space to be inserted is narrowed, there is no air flow, and the temperature in the imaging region may increase. In addition, the gradient coil itself may generate heat due to the amount of current flowing through the gradient coil in order to capture a high-resolution image, and the temperature in the imaging region may further increase. In order to prevent heat from being trapped in the imaging region, there has been a technique in which a fan is provided in the gantry and air is blown to the subject (for example, Patent Document 1).

JP-A-1-145050.

  The fan described in the cited document 1 is fixed to the gantry. For this reason, since the fan can only blow air in one direction, it has been difficult to release heat from a locally high temperature part.

  Therefore, an object of the present invention is to make the imaging region in the gantry appropriate temperature by blowing air to a region where the temperature is locally high in the imaging region in the gantry.

  A gantry including a static magnetic field generation source for forming a static magnetic field space, a couch having a top plate for placing and inserting a subject in the static magnetic field space, and placed on the top plate In a magnetic resonance imaging apparatus comprising a receiving means for receiving a nuclear magnetic resonance signal from the subject, a blower duct for sending air to an imaging region in the gantry, and a blowing direction of the blower duct are controlled. The air flow direction control means includes a plurality of temperature measurement means for measuring the temperature of the imaging region in the gantry, and the air flow direction control means is based on temperature information output from the plurality of temperature measurement means. The air blowing direction of the duct is set.

  In addition, the apparatus includes air flow control means for controlling the air flow output from the air duct, and the air flow control means sets the air flow based on temperature information output from the temperature measurement means. A plurality of the air ducts are provided, and each of the air ducts is directed to the same photographing area. Alternatively, a plurality of the air ducts are provided, and the plurality of air ducts are directed to different imaging regions.

  In this way, the temperature in the imaging area of the subject is monitored, the imaging area is controlled to be an appropriate temperature, and air is blown to a locally high temperature area in the imaging area in the gantry. The area can be brought to an appropriate temperature. Therefore, as a result, the subject is photographed comfortably at the time of photographing, and the subject is not forced to suffer.

  According to the present invention, the imaging region in the gantry can be brought to an appropriate temperature by blowing air to a region that is locally hot in the imaging region in the gantry.

  Embodiments of the present invention will be described with reference to the drawings. Note that components having the same function are denoted by the same reference symbols in the drawings for describing the embodiment of the present invention, and the repetitive description thereof is omitted.

  FIG. 1 shows an overall perspective view of a horizontal magnetic field type MRI apparatus according to the present invention. This MRI apparatus uses a NMR phenomenon to obtain a tomographic image of a subject. A gantry 31 that houses various devices for inducing a NMR phenomenon in the subject and receiving NMR signals is placed on the subject. A bed 32 with a top plate 36, a power source for driving various devices in the gantry 31 and a housing 33 for storing various control devices to be controlled, and processing the received NMR signals to reconstruct a tomographic image of the subject. The processing unit 34 is connected to each other by a power source / signal line 35. An operation panel 37 for operating the movement of the top plate 36 is disposed in the opening of the gantry 31. The gantry 31 and the bed 32 are disposed in a shield room that shields high-frequency electromagnetic waves and static magnetic fields, and the housing 33 and the processing device 34 are disposed outside the shield room.

  FIG. 2 shows a block configuration diagram in which the configuration of the MRI apparatus of FIG. 1 is disassembled for each more detailed function. As shown in FIG. 2, the MRI apparatus includes a static magnetic field generation system 2, a gradient magnetic field generation system 3, a transmission system 5, a reception system 6, a signal processing system 7, a sequencer 4, and a central processing unit (CPU). 8 and configured. The static magnetic field generation system 2 generates a uniform static magnetic field in the body axis direction (horizontal magnetic field method) in the space around the subject 1, and a normal or superconducting static magnetic field around the subject 1 The source is located. The static magnetic field generation system 2 is accommodated in the gantry 31.

  The gradient magnetic field generation system 3 includes a gradient magnetic field coil (hereinafter referred to as GC) 9 wound in three axial directions of X, Y, and Z, and a gradient magnetic field power source 10 that drives each GC 9. The gradient magnetic field power supply 10 of each coil is driven according to a command from the sequencer 4 described later, thereby applying gradient magnetic fields Gx, Gy, and Gz in the X, Y, and Z directions to the subject 1. More specifically, a slice direction gradient magnetic field pulse (Gs) is applied in one of X, Y, and Z to set a slice plane for the subject 1, and the phase encode direction gradient magnetic field is applied to the remaining two directions. A pulse (Gp) and a frequency encoding direction gradient magnetic field pulse (Gf) are applied, and position information in each direction is encoded in the echo signal. The GC 9 is accommodated in the gantry 31 and the gradient magnetic field power source 10 is accommodated in the casing 33.

  The sequencer 4 is a control means that repeatedly applies a high-frequency magnetic field pulse (hereinafter referred to as “RF pulse”) and a gradient magnetic field pulse in a predetermined pulse sequence, and operates under the control of the CPU 8 to collect tomographic image data of the subject 1. Various commands necessary for the transmission are sent to the transmission system 5, the gradient magnetic field generation system 3, and the reception system 6. Furthermore, the sequencer 4 includes means for measuring while changing the output of the RF pulse. The sequencer 4 is accommodated in the housing 33.

  The transmission system 5 irradiates an RF pulse to cause nuclear magnetic resonance to the nuclear spins of atoms constituting the biological tissue of the subject 1, and includes a high frequency oscillator 11, a modulator 12, a high frequency amplifier 13, and a transmission side It consists of a high frequency coil 14a. The high-frequency pulse output from the high-frequency oscillator 11 is amplitude-modulated by the modulator 12 at a timing according to a command from the sequencer 4, and the amplitude-modulated high-frequency pulse is amplified by the high-frequency amplifier 13 and then placed close to the subject 1. By supplying to the high frequency coil 14a, the subject 1 is irradiated with the RF pulse. In general, the high-frequency coil 14 a is accommodated in the gantry 31 and the others are accommodated in the housing 33.

  The receiving system 6 detects an echo signal (NMR signal) emitted by nuclear magnetic resonance of nuclear spins constituting the biological tissue of the subject 1, and receives a high-frequency coil 14b on the receiving side, a signal amplifier 15, and quadrature detection. And an A / D converter 17. The NMR signal of the response of the subject 1 induced by the electromagnetic wave irradiated from the high-frequency coil 14a on the transmission side is detected by the high-frequency coil 14b arranged close to the subject 1 and amplified by the signal amplifier 15, The signal is divided into two orthogonal signals by the quadrature phase detector 16 at the timing according to the command from the sequencer 4, and each signal is converted into a digital quantity by the A / D converter 17 and sent to the signal processing system 7.

  Generally, the device group constituting the receiving system 6 is accommodated in the gantry 31. Specifically, a receiving coil 14b for receiving an NMR signal emitted from the subject 1 is attached to the imaging part of the subject 1. The closer the receiving coil 14b is to the imaging region of the subject 1, the higher the S / N ratio of the NMR signal emitted from the subject 1. Further, when the sensitivity center of the receiving coil 14b is matched with the center of the imaging part, an image with a high S / N ratio without unevenness of sensitivity can be obtained. For this reason, a large number of receiving coils are prepared for each imaging region such as a receiving coil for the head, a receiving coil for the cervical spine for the cervical spine, and a receiving coil for the lumbar spine for the lumbar spine.

The signal processing system 7 includes an external storage device such as an optical disk 19 and a magnetic disk 18 and a display 20 including a CRT or the like. When data from the receiving system 6 is input to the CPU 8, the CPU 8 executes processing such as signal processing and image reconstruction, and displays the tomographic image of the subject 1 as a result on the display 20, and an external storage device On the magnetic disk 18 or the like. Note that the high-frequency coil 14 and the GC 9 on the transmission side may be installed facing the subject 1 in the static magnetic field space of the static magnetic field generation system 2 in which the subject 1 is inserted. The high-frequency coil 14b on the receiving side may be installed so as to face or surround the subject 1.
At present, the radionuclide to be imaged by the MRI apparatus is a hydrogen nucleus (proton) that is a main constituent material of the subject 1 as being widely used clinically. By imaging information on the spatial distribution of proton density and the spatial distribution of relaxation time in the excited state, the form or function of the human head, abdomen, limbs, etc. is imaged two-dimensionally or three-dimensionally.

Based on the above configuration, the subject 1 is placed on the top board 36, the receiving coil 14b is mounted, the switch on the gantry 31 operation panel 37 is operated, the top board 36 is inserted into the gantry 31, and imaging is performed. Start.
(First embodiment)
Next, a first embodiment in which the present invention is applied to the MRI apparatus will be described with reference to FIGS. FIG. 3 is a vertical sectional view of the gantry 31 of FIG. 1, which is a horizontal magnetic field type MRI apparatus. The static magnetic field generation source has a cylindrical shape, and a static magnetic field space (imaging region) is formed in the horizontal direction. The subject 1 is inserted into this space so that imaging for diagnosis can be performed.

  A blowing device 40 is installed at the tip (Z portion in the figure) of the cylindrical portion of the gantry 31. The blower fan device 441 and the blower fan device 442 having fans therein, the blower amount control device 41 for controlling the blower amount of the blower fan device 441 and the blower fan device 442, and the blower direction and the blower amount of the blowing device 40 are controlled. A ventilation control device 45 and a temperature control device 48 are provided in the lower part of the gantry 31.

  In the imaging area of the gantry 31, a plurality of temperature sensors 47 for measuring temperature are arranged. Specifically, as shown in FIG. 4, five temperature sensors 47 are provided in a circular shape in the cylindrical portion of the gantry 31. In order to measure the temperature around the subject 1, these temperature sensors 47 are arranged above the top surface of the top plate 36. As shown in FIG. 3, three groups of five temperature sensors 47 arranged in a circumferential shape are arranged in the horizontal direction.

  As shown in FIGS. 3 and 5, these temperature sensors 47 are connected to a temperature control device 48 by a signal cable 49. The temperature control device 48 analyzes the temperature distribution in the imaging region based on the temperature information measured by the temperature sensor 47. The temperature control device 48 is connected to the air blow control device 45, and controls the air blow control device 45 so that the inside of the photographing region becomes an optimum temperature. Note that the temperature control device 48 is connected to the CPU 8, and temperature control is possible from a console outside the shield room. In FIG. 5, the number of the temperature sensors 47 is four for drawing creation, but in the first embodiment, the number of the temperature sensors 47 is fifteen. In the first embodiment, when the number of temperature sensors 47 is greater than 15, a finer temperature distribution state can be analyzed.

  The air blowing control device 45 is connected to the air blowing direction control device 52 and the air blowing amount control device 41. The air blowing control device 45 gives an instruction about the air blowing direction to the air blowing direction control device 52, and gives an instruction about the air blowing amount to the air blowing amount control device 41.

  The air blowing direction control device 52 is connected to the vertical drive units 551 and 552 and the left and right drive units 561 and 562. The air blowing direction control device 52 controls the vertical driving units 551 and 552 and the left and right driving units 561 and 562, and controls the direction of the air outlets 591 and 592 of the air blowing ducts 531 and 532. Further, the blower amount control device 41 is connected to the blower fan devices 441 and 442. The blower amount control device 41 controls the blower amount of the blower fan devices 441 and 442.

  A blower hose 461 is connected to the blower fan device 441. A blower hose 462 is connected to the blower fan device 442. The wind generated by the blower fan devices 441 and 442 can be sent to the blowout device 40 via the blower hoses 461 and 462.

  FIG. 6 is an enlarged view of the blowing device 40 in FIG. The blow-out device 40 includes blower ducts 531 and 532, rods 541 and 542, vertical drive units 551 and 552, left and right drive units 561 and 562, and a blow direction control device 52. The air ducts 531 and 532 are hollow, and have flexibility enough to freely change the direction of the air outlets 591 and 592 in the gantry 31. Further, the air blowing control device 45 and a power source (not shown) are connected to the air blowing direction control device 52 by a signal cable 49.

  One end of the air duct 531 is an outlet 591, and the other end is connected to the air hose 461. A rod 541 is fixed to the side surface of the air duct 531 near the air outlet 591. The rod 541 is connected to a vertical drive unit 551 that moves the blowout port 591 in the vertical direction and a left-right drive unit 561 that moves the blowout port 591 in the horizontal direction. The vertical drive unit 551 rotates the rod 541 around one end of the rod 541 and moves the outlet 591 in the vertical direction. Further, the left / right drive unit 561 moves the entire vertical drive unit 551 in the left / right direction, and moves the rod 541 in the left / right direction. The outlet 591 of the air duct 531 connected to the rod 541 moves in the left-right direction together with the rod 541.

  Similarly to the air duct 531, one end of the air duct 532 is an outlet 592 and the other end is connected to the air hose 462. A rod 542 is fixed to the side surface of the air duct 532 near the air outlet 592. The rod 542 is connected to a vertical drive unit 552 that moves the blowout port 592 in the vertical direction and a left-right drive unit 562 that moves the blowout port 592 in the left-right direction. The vertical drive unit 552 rotates the rod 542 around one end of the rod 542 and moves the outlet 592 in the vertical direction. Further, the left / right drive unit 562 moves the entire vertical drive unit 552 in the left / right direction, and moves the rod 542 in the left / right direction. The air outlet 592 of the air duct 532 connected to the rod 542 moves in the left-right direction together with the rod 542.

  The operation of the first embodiment will be described. At the opening of the gantry 31 or outside, the subject 1 and the receiving coil 14b are placed on the top plate 36 of the bed 32, and the top plate 36 is electrically moved so that the imaging center is at the center of the imaging space. The temperature in the imaging region is measured by a plurality of temperature sensors 47 arranged from the time when the top plate 36 is moved. Temperature information from the temperature sensor 47 is received by the temperature control device 48, and the temperature control device 48 grasps the temperature distribution in the imaging region from the received temperature information.

  Based on the temperature distribution grasped by the temperature control device 48, the air blowing control device 45 sets the air blowing direction and the air blowing amount. The blower control device 45 sets a blow direction control signal and a blow amount control signal based on the temperature information. The blowing direction control signal is transmitted to the blowing direction control device 52, and the blowing amount control signal is transmitted to the blowing amount control device.

  The blowing direction control device 52 that has received the blowing direction control signal controls the outlet driving devices 551, 561, 552, and 562 of the blowing direction control device 52 and moves the rods 541 and 542 connected to the blowing ducts 531 and 532 so as to blow into the high temperature region. The direction of the outlets 591 and 592 of the air ducts 531 and 532 is changed.

  The air flow control device 41 that has received the air flow control signal controls the rotational speed of the fan motors of the blower fan devices 441 and 442, and adjusts the air flow by varying the rotational speed. The blower fan devices 441 and 442 have at least one fan. When the air ducts 531 and 532 are provided, finer temperature control becomes possible by individually controlling the rotational speed.

  Here, the operation of the first embodiment will be described in detail. As shown in FIGS. 3 and 4, the imaging area in the gantry 31 is divided into a plurality of area sections corresponding to the installation location of the temperature sensor 47. Specifically, as shown in FIG. 4, the cylindrical surface of the cylindrical portion is divided into A to E corresponding to the installation location of the temperature sensor 47, and the horizontal plane is divided into a to i as shown in FIG. The That is, the imaging region in the gantry 31 is divided into 15 regions from region (A, a) to region (E, i) so as to cover the subject 1.

  The temperature described in the temperature sensor 47 shown in FIG. 7 indicates the temperature measured by the temperature sensor 47. The temperature control device 48 grasps the temperature distribution of the imaging region based on the temperature information measured by the temperature sensor 47. In the case of FIG. 7, the temperature control device 48 grasps that the region (D, e) is 30 ° C. and the highest temperature, and then the region (E, h) is 28 ° C. and the temperature is high. The other plurality of regions are 26 ° C. and 23 ° C. Here, 23 ° C. is an appropriate temperature.

  The temperature control device 48 grasps the relationship between these regions and the temperature, and sets a control signal for the blowing direction and the blowing amount so that the air is blown to the substantially central portion of the highest temperature region (D, e). The blowout direction of the blowout ports 591 and 592 of the blower ducts 531 and 532 and the position of the substantially central portion of the regions (A, a) to (E, i) are associated in advance, and the blower direction control device 52 controls this correspondence. It is memorized as a signal. The blowing direction control signal here is a control signal that is blown to the substantially central portion of the region (D, e) where the temperature is highest.

  For example, if the temperature measured by the temperature sensor 47 is 30 ° C. or higher, the air flow control signal increases the air flow. If the temperature is 27 ° C. to 29 ° C., the air flow control signal is relatively large, and may be 24 ° C. to 26 ° C. For example, the air flow rate is set low. Thus, the rotation speed of the fan motor is controlled in accordance with the temperature of the temperature sensor 47. The air volume control signal here is a control signal that increases the air volume because the region (D, e) is 30 ° C. or higher.

  The air blowing direction control device 52 that has received the air blowing direction control signal controls the blowout port driving devices 551, 561, 552, and 562, moves the rods 541 and 542 connected to the air blowing ducts 531 and 532, and blows air to the substantially central portion of the region (D, e). Thus, the direction of the outlets 591 and 592 of the respective air ducts 531 and 532 is changed. In addition, the air flow control device 41 that has received the air flow control signal controls to increase the number of rotations of the motors of the fans of the air blowing fan devices 441 and 442.

  When the temperature sensor 47 in the region (D, e) is measured at an appropriate temperature of 23 ° C., the temperature controller 48 grasps the relationship between these regions and the temperature, and then sends air to the region (E, h) where the temperature is the next highest. Thus, the control signal for the air blowing direction and the air flow rate is set, and air is sent to the area (E, h) using the air blowing direction control device 52 and the air flow rate control device 41 in the same manner as described above.

  In this example, the air is blown sequentially to the substantially central part of the region (D, e) and the region (E, h), but the air is blown between the region (D, e) and the region (E, h). Also good.

  When the temperature sensor 47 in the area (D, e) is measured at an appropriate temperature of 23 ° C, the air is blown to the area of 26 ° C, and all the temperature sensors 47 in the areas (A, a) to (E, i) are at 23 ° C. Repeat the blow so that it is measured.

  When all the temperature sensors 47 in the regions (A, a) to (E, i) are measured at 23 ° C., the temperature control device 48 stops the transmission of the control signal for the blowing direction and the blowing amount, and stops blowing. . In addition, since the temperature of the region (A, a) to the region (E, i) increases with the lapse of the photographing time, the temperature of the region (A, a) to the region (E, i) is always maintained at 23 ° C. In addition, the breeze may continue to flow sequentially from the region (A, a) to the region (E, i).

  As described above, by controlling the blowing direction and the blowing amount by the temperature control device 48, the imaging region in the gantry 31 can be set to an appropriate temperature. Therefore, the subject can be comfortably photographed without causing pain or anxiety, and as a result, the time for photographing can be shortened.

Furthermore, since the temperature control device 48 is also connected to the CPU 8, it is possible to control the temperature from the console outside the shield room, and therefore, it is possible to cope with a change in the comfortable temperature due to individual differences.
(Second embodiment)
Next, a second embodiment will be described with reference to FIG. The difference from the first embodiment is that the two air outlets are directed in different directions and blown into different areas.

  In the case of FIG. 8, the region (D, e) is 30 ° C., the highest temperature, and then the region (E, h) is 28 ° C., the temperature is high. The temperature control device 48 grasps the relationship between these regions and the temperature, and the air blowing direction so that the air is blown to a substantially central portion of the highest temperature region (D, e) and then the highest temperature region (E, h). And set the control signal of air flow. Here, the blowing direction control signal is a control signal that is blown to a substantially central portion of the region (D, e) and the region (E, h).

  The air blowing direction control device 52 that has received the air blowing direction control signal controls the air outlet driving devices 551 and 561 and moves the rod 541 connected to the air blowing duct 531 to blow air to the substantially central portion of the region (D, e). As described above, the direction of the outlet 591 of each air duct 531 is changed. Further, the air blowing direction control device 52 controls the air outlet driving devices 552 and 562, and moves the rod 542 connected to the air blowing duct 532 so that the air is blown to the substantially central portion of the region (E, h). The direction of the air outlet 592 of the air duct 532 is changed.

Then, if the temperature sensor 47 in the region (D, e) or the region (E, h) is measured at an appropriate temperature of 23 ° C., the temperature control device 48 sets the blowing direction so that the air is blown to the next highest temperature region. A control signal for the air flow rate is set, and air is sent to that area using the air flow direction control device 52 and the air flow rate control device 41 in the same manner as described above.
(Third embodiment)
Next, a third embodiment will be described with reference to FIG. The difference between the first embodiment and the second embodiment is that three air ducts 591, 592, 593 are provided.

  FIG. 9 is an enlarged view of the blowing device 40 in FIG. The blow-out device 40 includes blower ducts 531, 532, 533, rods 541, 542, 543, vertical drive units 551, 552, 553, and a blow direction control device 52.

  One end of each of the air ducts 531,532,533 is a blowout port 591,592,593, and the other end is connected to the air blowing hoses 461,462,463. Rods 541, 542, and 543 are fixed to the side surfaces of the air ducts 531, 532, and 533 near the outlets 591, 592, and 593. The rods 541, 542, and 543 are connected to vertical drive units 551, 552, and 553 that move the air outlets 591, 592, and 593 in the vertical direction. The vertical drive units 551, 552, and 553 rotate the rods 541, 542, and 543 around one end of the rods 541, 542, and 543, and move the outlets 591, 592, and 593 in the vertical direction. The wind generated by the blower fan devices 441, 442, 443 (not shown) is sent to the blowout ports 591, 592, 593 of the blower ducts 531, 532, 533 through the blower hoses 461, 462, 463.

  In the blow-out device 40 configured as described above, an area arranged in the horizontal direction of the imaging area corresponds to an arrangement of the air ducts 531, 532, and 533. Specifically, the air duct 531 corresponds to the region (D, d) to the region (D, f) and the region (E, g) to the region (E, i). The air duct 532 corresponds to the region (C, a) to the region (C, c). The air duct 533 corresponds to the region (B, d) to the region (B, f) and the region (A, g) to the region (A, i).

  By moving the outlet 591 of the air duct 531 in the vertical direction using the vertical drive unit 551, the region (D, d) to the region (D, f) and the region (E, g) to the region (E, i ) Can be blown. Further, by using the vertical drive unit 552, the blowout port 592 of the blower duct 532 is moved in the vertical direction, so that air can be blown into the region (C, a) to the region (C, c). By using the vertical drive unit 553 to move the air outlet 593 of the air duct 533 in the vertical direction, the region (B, d) to the region (B, f) and the region (A, g) to the region (A, i ) Can be blown. As described above, in the third embodiment, the region arranged in the horizontal direction of the imaging region and the arrangement of the air ducts 531, 532, and 533 correspond to each other, and thus the left and right drive unit used in the first embodiment is not necessary.

1 is an overall configuration diagram of an MRI apparatus according to the present invention. 1 is a block diagram of an MRI apparatus according to the present invention. 1 is a vertical sectional view of an MRI apparatus to which the present invention is applied. 1 is a vertical sectional view of an MRI apparatus to which the present invention is applied. The block diagram of the temperature control of the MRI apparatus to which this invention is applied. The detailed drawing of the blowing apparatus of the MRI apparatus to which this invention is applied. FIG. 2 is a detailed view of the first embodiment of the present invention. FIG. 5 is a detailed view of a second embodiment of the present invention. Detailed view of the third embodiment of the present invention.

Explanation of symbols

  1 subject, 2 static magnetic field generation system, 3 gradient magnetic field generation system, 4 sequencer, 5 transmission system, 6 reception system, 7 signal processing system, 8 central processing unit (CPU), 9 gradient magnetic field coil, 10 gradient magnetic field power supply, 11 High-frequency transmitter, 12 modulator, 13 high-frequency amplifier, 14a high-frequency coil (transmitting coil), 14b high-frequency coil (receiving coil), 15 signal amplifier, 16 quadrature detector, 17 A / D converter, 18 magnetic disk, 19 Optical disk, 20 Display, 31 Gantry, 32 Table, 33 Case, 34 Processing device, 35 Power supply line, Signal line, 36 Top panel, 37 Operation panel, 40 Blowout device, 41 Airflow control device, 45 Airflow control device, 47 temperature sensor, 48 temperature control device, 52 air flow direction control device.

Claims (4)

A gantry including a static magnetic field generation source for forming a static magnetic field space; a bed having a top plate for placing and inserting a subject in the static magnetic field space; In a magnetic resonance imaging apparatus comprising a receiving means for receiving a nuclear magnetic resonance signal from the subject,
An air duct for blowing air to the imaging area in the gantry, an air blowing direction control means for controlling the air blowing direction of the air duct, and a plurality of temperature measuring means for measuring the temperature of the imaging area in the gantry, The magnetic resonance imaging apparatus, wherein the air blowing direction control means sets the air blowing direction of the air blowing duct based on temperature information output from the plurality of temperature measuring means.   A blast volume control means for controlling the blast volume output from the blast duct is provided, and the blast volume control means sets the blast volume based on temperature information output from the temperature measurement means. 2. The magnetic resonance imaging apparatus according to claim 1, wherein:   2. The magnetic resonance imaging apparatus according to claim 1, wherein a plurality of the air ducts are provided, and each of the plurality of air ducts is directed to the same imaging region.   2. The magnetic resonance imaging apparatus according to claim 1, wherein a plurality of the air ducts are provided, and the plurality of air ducts are directed to different imaging regions.

Images