Receiving coil device and magnetic resonance imaging device

Abstract

The invention provides a receiving coil device capable of automatically winding a receiving coil on an examination part of a subject and unwinding the receiving coil, and a magnetic resonance imaging device. A reception coil device, which is provided in a magnetic resonance imaging device and receives a nuclear magnetic resonance signal, is provided with: a reception coil (203) that receives the nuclear magnetic resonance signal; and a flexible tape (210) that accommodates the receiving coil (203) and is partially fixed to an upper plate (132) of the bed body, the flexible tape (210) being changed in shape by the supply and / or discharge of the fluid and winding the receiving coil (203) around the examination site of the subject (102) on the bed body or releasing the winding of the receiving coil (203).

Description

Technical Field

[0001] The present invention relates to a receiving coil device and a magnetic resonance imaging device, and in particular to a technology for automatically setting a receiving coil at an examination site of an examinee. Background Art

[0002] In an MRI examination using a magnetic resonance imaging device (MRI (Magnetic Resonance Imaging) device), radio frequency (RF: Radio Frequency) waves at the resonance frequency inherent to the element are irradiated onto the examination area of ​​the subject, and the generated nuclear magnetic resonance signals (NMR (Nuclear Magnetic Resonance: nuclear magnetic resonance) signals) are received by a receiving coil (also called an "RF coil"), and an image (MRI image) is generated based on the received NMR signals.

[0003] Before the MRI examination begins, the technician needs to manually set the receiving coil at the examination site of the patient while paying attention to the patient's posture, positioning, the presence of MRI-contraindicated items such as metal, and the presence of cable loops that may cause burns.

[0004] Since the receiving coil is manually set in this way, it is troublesome and becomes a factor that prolongs the inspection time. Conventionally, there has been a demand for simplifying the receiving coil setting and reducing the burden.

[0005] Patent Document 1 describes a module for mounting a local coil (receiving coil) on a patient to perform magnetic resonance diagnosis.

[0006] The unit described in Patent Document 1 includes a receiving coil (local coil) configured to receive NMR signals and a support device configured to accommodate the local coil and attach the local coil to a patient.

[0007] The supporting device is configured as a cushion filled with gas and has a device for changing the gas pressure, and the shape of the cushion changes in association with the gas pressure. That is, the supporting device presses the local antenna against the patient according to the change in shape of the cushion caused by the change in gas pressure.

[0008] Specifically, the buffer part is composed of a substrate formed as an elastic plastic plate, a non-breathable hard foam with a gap bonded to the substrate, and a breathable soft foam filled in the gap. The unit formed by the substrate, the hard foam and the soft foam is pressed into the non-breathable cover and vacuum-sealed.

[0009] Furthermore, by exhausting the air in the mask, the air-permeable soft foam shrinks, and the shape of the cushioning member changes according to the relationship between the shrinking soft foam and the non-shrinking non-air-permeable hard foam, so that the local coil is deformed to match the patient's body. The degree of deformation or deformation pressure is adjusted according to the vacuum degree generated when the air is exhausted.

[0010] In addition, a device for fixing a high-frequency coil to a subject is proposed in Patent Document 2. The high-frequency coil has a flexible substrate and an outer casing provided to cover the substrate, and foam beads are provided between the flexible substrate and the outer casing to fill the gap to such an extent that air exists in the gap. After the high-frequency coil is mounted on the subject by the operator, the air in the outer casing is sucked out and the high-frequency coil is fixed to the shape of the subject.

[0011] Patent Document 1: Japanese Patent Application Publication No. 2009-11837

[0012] Patent Document 2: Japanese Patent Application Publication No. 2011-30828

[0013] According to the component described in Patent Document 1, the air in the cover of the support device can be discharged (suctioned) and the shape of the cushioning member can be changed according to the vacuum degree in the cover so that the local coil can be deformed (wound) to match the patient's body. However, the winding cannot be automatically undone and a valve needs to be opened to wait until the vacuum degree in the cover becomes the ambient air pressure.

[0014] Furthermore, since the components are not fixed to the bed, the technician needs to arrange the components according to the examination part of the subject, which takes time.

[0015] Furthermore, the device described in Patent Document 2 can fix the high-frequency coil along the surface shape of the subject (make it close and fixed) by sucking the air from the external part of the high-frequency coil, but the operator needs to install the high-frequency coil on the subject in advance (before the air from the external part is sucked), which takes time. Summary of the invention

[0016] The present invention has been made in view of such circumstances, and an object of the present invention is to provide a receiving coil device and a magnetic resonance imaging apparatus that can automatically wind a receiving coil around an examination site of a subject and can unwind the coil.

[0017] The invention according to a first aspect is a receiving coil device which is installed in a magnetic resonance imaging apparatus and receives nuclear magnetic resonance signals. The receiving coil device comprises: a receiving coil which receives the nuclear magnetic resonance signals; and a flexible belt which accommodates the receiving coil and is partially fixed to a bed, wherein the flexible belt changes shape by supplying and / or discharging a fluid and winds the receiving coil around an examination site of a subject on the bed or unwinds the receiving coil.

[0018] According to the first aspect of the present invention, the operator only needs to position the examination area of ​​the subject with the flexible belt fixed to the bed before the MRI examination, and then the receiving coil can be automatically wound around the examination area, and the receiving coil can be automatically unwound after the MRI examination is completed.

[0019] Preferably, in the receiving coil device involved in the second embodiment of the present invention, in the first embodiment, the flexible belt is composed of a first layer and a second layer joined together, the first layer accommodates the receiving coil, and the second layer has a bag-like structure and is bent or stretched by the fluid supplied to or discharged from the bag-like structure, the flexible belt bends when the fluid is supplied to the bag-like structure to wrap the receiving coil around the inspection part, and the receiving coil is unwound when the fluid is discharged from the bag-like structure.

[0020] Preferably, in the receiving coil device according to the third aspect of the present invention, in the second aspect, the first layer includes a first pocket-shaped structure portion that accommodates the receiving coil.

[0021] Preferably, in the receiving coil device according to the fourth aspect of the present invention, in the second aspect or the third aspect, the first layer is arranged on the inner peripheral side of the curved flexible belt. Thereby, the receiving coil can be wound closer to the examination site of the subject.

[0022] Preferably, in the receiving coil device involved in the fifth embodiment of the present invention, in the first embodiment, the flexible belt is composed of a first layer, a second layer and a third layer joined together, the first layer accommodates the receiving coil, the second layer has a second bag-like structure portion and is stretched by the fluid supplied to the second bag-like structure portion, the third layer has a third bag-like structure portion and is bent by the fluid supplied to the third bag-like structure portion, the flexible belt stretches the receiving coil and is at least able to release the winding around the inspection part when the fluid is discharged from the third bag-like structure portion and supplied to the second bag-like structure portion, and bends when the fluid is supplied to the third bag-like structure portion to wind the receiving coil around the inspection part.

[0023] Preferably, in the receiving coil device according to the sixth aspect of the present invention, in the fifth aspect, the flexible belt is overlapped and joined to the first layer, the second layer and the third layer in sequence from the innermost circumference of the flexible belt, or the second layer, the first layer and the third layer are overlapped and joined in sequence from the innermost circumference of the flexible belt.

[0024] Preferably, in the receiving coil device according to the seventh aspect of the present invention, in the fifth aspect or the sixth aspect, the first layer is arranged at the innermost circumference of the curved flexible band, and the second layer and the third layer are arranged at positions closer to the outer circumference than the first layer. Thus, the receiving coil can be wound closer to the examination site of the subject.

[0025] Preferably, in the receiving coil device according to the eighth aspect of the present invention, in any one of the fifth to seventh aspects, the first layer includes a first pocket-shaped structure portion that accommodates the receiving coil.

[0026] Preferably, the receiving coil device involved in the 9th mode of the present invention, in any one of the 2nd to 4th modes, comprises: a fluid pressure circuit, having a fluid pressure source for supplying and / or discharging fluid, a hose arranged between the fluid pressure source and the bag-like structure part, and a solenoid valve arranged on the hose to switch the direction of the fluid flowing through the hose; and a control unit, which controls the fluid pressure source and the solenoid valve, and when the control unit receives a winding instruction of the receiving coil, controls the fluid pressure source and the solenoid valve so that the fluid is supplied from the fluid pressure source to the bag-like structure part via the solenoid valve and the hose to wind the receiving coil around the inspection part, and when the control unit receives a winding release instruction of the receiving coil, the fluid is discharged from the bag-like structure part via the hose and the solenoid valve to release the winding of the receiving coil around the inspection part.

[0027] Preferably, the receiving coil device involved in the tenth aspect of the present invention, in any one of the fifth to eighth aspects, comprises: a fluid pressure circuit having a fluid pressure source for supplying and / or discharging a fluid, a first hose and a second hose arranged between the fluid pressure source and the second bag-like structure portion and the third bag-like structure portion, and an electromagnetic valve arranged in the first hose and the second hose to switch the direction of the fluid flowing through the first hose and the second hose; and a control unit that controls the fluid pressure source and the electromagnetic valve, and when receiving a winding instruction of the receiving coil, the control unit controls the fluid pressure source and the electromagnetic valve so that the fluid is discharged from the second bag-like structure portion via the first hose and the electromagnetic valve, and the fluid is supplied from the fluid pressure source via the electromagnetic valve and the second hose to the third bag-like structure portion to wind the receiving coil around the inspection portion, and when receiving a winding release instruction of the receiving coil, the fluid is discharged from the third bag-like structure portion via the second hose and the electromagnetic valve, and the fluid is supplied from the fluid pressure source via the electromagnetic valve and the first hose to the second bag-like structure portion to release the winding of the receiving coil around the inspection portion.

[0028] Preferably, in the receiving coil device according to the eleventh aspect of the present invention, in the ninth aspect or the tenth aspect, the control unit receives an instruction to raise the bed or a first time point during the control of raising the bed as an instruction to wind the receiving coil. Thus, even if the operator does not give an instruction to wind the receiving coil, the receiving coil can be automatically wound around the examination site at a desired time point.

[0029] Preferably, in the receiving coil device according to the twelfth aspect of the present invention, in the ninth aspect or the tenth aspect, the control unit receives an instruction to pull out the bed from the gantry of the magnetic resonance imaging device or a second time point during the control of pulling out the bed as an instruction to unwind the receiving coil. Thus, even if the operator does not issue an instruction to unwind the receiving coil, the winding of the receiving coil around the examination site can be automatically unwound at a desired time point.

[0030] The invention according to a thirteenth aspect is a magnetic resonance imaging apparatus including the receiving coil device according to any one of the first to twelfth aspects.

[0031] Effects of the Invention

[0032] According to the present invention, the receiving coil can be automatically wound around the examination area of ​​the subject on the bed and the winding of the receiving coil can be automatically released, thereby simplifying the setting of the receiving coil and reducing the burden on the operator. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a perspective view showing the appearance of a magnetic resonance imaging apparatus (MRI apparatus) including a receiving coil device according to the present invention.

[0034] Figure 2 Yes means Figure 1 A diagram showing a schematic structure of the interior of an MRI apparatus.

[0035] Figure 3 It is a diagram showing a first embodiment of a receiving coil device according to the present invention.

[0036] Figure 4 It is a diagram showing a main part of a second embodiment of a receiving coil device according to the present invention.

[0037] Figure 5 It will constitute Figure 4 The expanded view of the flexible belt is shown with the pocket-like structures arranged separately.

[0038] Figure 6 This is a conversion diagram showing the outline of the action of the flexible belt accommodating the receiving coil and the movement of the bed.

[0039] Figure 7 Yes means Figure 4 A diagram showing an example of a driving and control unit for a flexible belt.

[0040] Explanation of symbols

[0041] 100-MRI device, 102-subject, 110-gantry, 120-cavity, 130-bed, 132-upper board, 140, 230, 260-control unit, 150, 232-operation unit, 200-receiving coil device, 203-receiving coil, 210-flexible belt, 220-fluid pressure circuit, 240-flexible belt. DETAILED DESCRIPTION

[0042] Hereinafter, preferred embodiments of a receiving coil device and a magnetic resonance imaging apparatus according to the present invention will be described with reference to the accompanying drawings.

[0043] [Appearance of MRI device]

[0044] Figure 1 It is a perspective view showing the appearance of a magnetic resonance imaging apparatus (MRI apparatus) including a receiving coil device according to the present invention.

[0045] Figure 1 The MRI apparatus 100 shown includes a gantry 110 , a bed 130 including an upper plate 132 disposed in front of a cavity 120 which is a cylindrical imaging space provided in the gantry 110 , and a receiving coil device 200 partially fixed to the bed 130 .

[0046] [Internal structure of MRI device]

[0047] Figure 2 Yes means Figure 1 A diagram showing a schematic structure of the interior of an MRI apparatus.

[0048] like Figure 2 As shown, the MRI apparatus 100 includes: a static magnetic field generating magnet 104, which generates a uniform static magnetic field in an imaging space where a subject 102 is arranged; a gradient magnetic field coil 106, which generates a gradient magnetic field in the imaging space; an RF (Radio Frequency) coil (transmitting coil) 108, which generates a high-frequency magnetic field that causes the nuclei of atoms constituting the tissue of the subject 102 to generate nuclear magnetic resonance signals (NMR signals); and a receiving coil device 200, which includes a receiving coil for detecting the NMR signals generated from the subject 102.

[0049] A portion of the receiving coil device 200 is fixed to the upper plate 132 ( Figure 1 ). The subject 102 is usually arranged in the imaging space in a state of lying on the upper plate 132 of the bed 130. In addition, the details of the receiving coil device 200 will be described later.

[0050] The sequencer 118 sends commands to the high-frequency magnetic field generator 112 and the gradient magnetic field power supply 116 according to the imaging sequence (pulse sequence) to generate a high-frequency magnetic field and a gradient magnetic field respectively. The generated high-frequency magnetic field is applied to the subject 102 as a pulsed high-frequency magnetic field (RF pulse) through the transmitting coil 108. The NMR signal generated from the subject 102 is received by the receiving coil device 200 and detected by the receiver 114.

[0051] The gradient magnetic field coil 106 is composed of gradient magnetic field coils in three directions, namely, X, Y, and Z, and generates gradient magnetic fields in each direction according to a signal from a gradient magnetic field power supply 116 .

[0052] In the receiver 114, the nuclear magnetic resonance frequency (detection reference frequency f0) serving as a detection reference is set by the sequencer 118. The sequencer 118 controls each unit so that it operates at a pre-programmed time point and intensity. Among the programs, the program that particularly records the RF pulse, the gradient magnetic field, the time point and intensity of signal reception is called a pulse sequence.

[0053] Various pulse sequences are known depending on the purpose, and detailed description thereof will be omitted here.

[0054] The control unit 140 receives the signal detected by the receiver 114 and performs various signal processing such as image reconstruction while controlling the operation of the MRI apparatus 100 via the sequencer 118. In addition, the receiver 114 performs quadrature phase detection on the echo signal, which is an analog wave, based on the set detection reference frequency f0, converts it into raw data, and transmits it to the control unit 140. The raw data is also called an echo signal or measurement data.

[0055] The control unit 140 can be constituted by a computer. The computer used for the control unit 140 may be a personal computer or a workstation.

[0056] The control unit 140 receives various instruction inputs from the operation unit 150 , centrally controls each unit of the MRI apparatus 100 , and performs processing such as inverse Fourier transform of the echo signals in the spatial frequency domain received via the sequencer 118 to convert them into real-space images, thereby generating an MRI image.

[0057] The operation unit 150 includes a mouse, a keyboard, and the like, and functions as a part of a GUI (Graphical User Interface) that receives input from an operator using a display operation window of a display (not shown).

[0058] That is, the operation unit 150 and the display function as a GUI for the operator to input the start, stop (pause), selection of a pulse sequence, imaging conditions, processing conditions, etc. of the MRI apparatus 100. Furthermore, the operation unit 150 of this example functions as an operation unit (operation button) used when the operator raises the bed 130 (upper plate 132) at the start of an examination or when the subject pulls the bed 130 (upper plate 132) out of the gantry 110 at the end of an examination.

[0059] [Receiving coil device]

[0060] <First embodiment>

[0061] Figure 3 It is a diagram showing a first embodiment of a receiving coil device according to the present invention.

[0062] Figure 3 The receiving coil device 200 shown is composed of a receiving coil 203 , a flexible belt 210 , a fluid pressure circuit 220 , a control unit 230 , and an operating unit 232 .

[0063] The receiving coil 203 is formed of, for example, a flexible wiring pattern, and is freely windable along the examination site of the subject 102. During the examination, a nuclear magnetic resonance signal (NMR signal) received by the receiving coil 203 is transmitted to the receiver 114 via the amplifier 205.

[0064] A fixed portion 210A as a part of the flexible belt 210 is fixed to the bed 130 (upper plate 132 ).

[0065] The flexible belt 210 is formed by joining a first layer having a first bag-like structure 202 accommodating a receiving coil 203 and a second layer having a bag-like structure 204 and being bent or stretched by a fluid supplied to or discharged from the bag-like structure 204. In this example, the fluid supplied to or discharged from the bag-like structure 204 is air, but the present invention is not limited thereto.

[0066] A plurality of folds are formed on the side surface of the bag-like structure 204 opposite to the first layer (first bag-like structure 202), and the folds are expanded when compressed air is supplied to the bag-like structure 204 and the inside of the bag-like structure 204 is pressurized. Thus, the bag-like structure 204 deforms in such a way that the flexible belt 210 is bent with the first layer (receiving coil 203) facing the inside by the area difference between the inner surface on the first layer side and the outer surface having the folds.

[0067] That is, the flexible belt 210 is centered on the fixing portion 210A. Figure 3 The two ends of the middle part move (rise) in the direction of arrow A and are wrapped around the subject 102.

[0068] On the other hand, when air is exhausted from the bag-like structure 204 in a state where air is supplied to the bag-like structure 204 and the flexible belt 210 is wrapped around the subject 102 , the wrapping force of the bag-like structure 204 disappears.

[0069] Thus, the flexible belt 210 moves (descends) in the direction of arrow B to stretch along the upper plate 132. Figure 3 As shown, the flexible band 210 is stretched and the winding of the receiving coil 203 is unwound.

[0070] In this way, the flexible belt 210 changes shape by supplying and / or exhausting contraction air to the bag-like structure 204 and winds the receiving coil around the examination site of the subject 102 on the bed 130 or unwinds the receiving coil.

[0071] The fluid pressure circuit 220 is composed of a pressure increasing and decreasing pump 221 , a hose 222 , a solenoid valve 224 , a pressure sensor 226 and a pressure reducing valve 228 .

[0072] The pressure adding and subtracting pump 221 acts as a fluid pressure source for supplying and / or discharging fluid. It is a pressure source for supplying air to the bag-like structure part 204 of the flexible belt 210 to bend the flexible belt 210 or discharging (sucking) air from the bag-like structure part 204 to stretch the flexible belt 210.

[0073] The hose 222 is a pipe that connects the air supply and exhaust port of the bag-like structure portion 204 of the flexible belt 210 and the pressure increasing and decreasing pump 221 .

[0074] The solenoid valve 224 is a two-position two-way solenoid valve disposed on the hose 222. The solenoid valve 224 opens when the solenoid 224A is energized to switch the supply or discharge of air to the bag-like structure 204 through the hose 222, and closes when the solenoid 224A is deenergized to block the flow of air.

[0075] The pressure sensor 226 detects the pressure in the bag-like structure 204 , and outputs a pressure signal indicating the detected pressure to the control unit 230 .

[0076] The pressure reducing valve 228 opens when the pressure in the bag-like structure 204 reaches an abnormal pressure, and functions as a safety valve for exhausting air.

[0077] The control unit 230 controls the pressure adding and subtracting pump 221 and the electromagnetic valve 224 according to the winding instruction of the receiving coil 203 or the winding release instruction of the receiving coil 203 from the operating unit 232, and winds the receiving coil 203 around the examination part of the subject 102 or releases the winding of the receiving coil 203 around the examination part.

[0078] That is, when the control unit 230 receives the winding instruction of the receiving coil 203 from the operation unit 232, the electromagnetic valve 224 is opened, and then the pressure adding and subtracting pump 221 is driven and controlled so that the compressed air is ejected from the pressure adding and subtracting pump 221. Then, when the control unit 230 detects that the pressure in the bag-like structure 204 of the flexible belt 210 reaches a preset reference pressure based on the detection signal of the pressure sensor 226, the pressure adding and subtracting pump 221 is stopped, and then the electromagnetic valve 224 is closed.

[0079] Thereby, the control unit 230 can automatically wind the receiving coil 203 together with the flexible belt 210 around the examination site of the subject 102 .

[0080] In addition, the reference pressure is preferably set to a degree that the flexible belt 210 (receiving coil 203 ) is bent and wrapped around the examination site of the subject 102 and closely adheres to the examination site to a level that does not hinder blood flow in the examination site.

[0081] On the other hand, when the control unit 230 receives an instruction to unwind the receiving coil 203 from the operation unit 232, the solenoid valve 224 is opened, and then the pressure adding and subtracting pump 221 is driven to discharge (suction) the air in the bag-like structure 204. Then, when the control unit 230 detects that the pressure in the bag-like structure 204 of the flexible belt 210 has reached or below the atmospheric pressure based on the detection signal of the pressure sensor 226, the pressure adding and subtracting pump 221 is stopped, and then the solenoid valve 224 is closed.

[0082] Thus, the control unit 230 can extend the receiving coil 203 together with the flexible belt 210 and automatically release the receiving coil 203 from being wound around the examination site.

[0083] In addition, in this example, the signal cable of the receiving coil 203 and the hose 222 connected to the bag-like structure portion 204 extend and protrude below the upper plate 132 via the fixing portion 210A of the flexible belt 210, but of course, the wiring and piping are performed in such a way that the signal cable of the receiving coil 203 and the hose 222 do not hinder the movement of the upper plate 132 when the bed 130 (upper plate 132) rises and falls and when the cavity 120 of the upper plate 132 enters and exits.

[0084] Furthermore, the signal cable and hose 222 of the receiving coil 203 from the flexible belt 210 are not limited to being led into the bed 130 via the fixed portion 210A of the flexible belt 210 . For example, a portion of the signal cable and hose 222 of the receiving coil 203 may be arranged along the upper plate 132 and the bed 130 .

[0085] <Second embodiment>

[0086] Figure 4This is a diagram showing a main part of a second embodiment of a receiving coil device according to the present invention, and shows a state in which a flexible belt constituting the receiving coil device is wound around a subject.

[0087] Figure 4 The flexible band 240 of the receiving coil device shown is composed of a first layer having a first bag-like structure portion 242 for accommodating the receiving coil 203, a second layer having a second bag-like structure portion 244 and stretched by a fluid supplied to the second bag-like structure portion 244, and a third layer having a third bag-like structure portion 246 and bent by a fluid supplied to the third bag-like structure portion 246.

[0088] Figure 5 It will constitute Figure 4 The expanded view of the flexible belt is shown with the pocket-like structures arranged separately.

[0089] like Figure 5 As shown, the first bag-like structure portion 242 formed on the innermost peripheral side of the flexible belt 240 has the shortest length, and then the second bag-like structure portion 244 and the third bag-like structure portion 246 become longer in this order.

[0090] Furthermore, both ends of the first bag-like structure portion 242 and the second bag-like structure portion 244 are joined at end points 243A and 243B, respectively, and both ends of the second bag-like structure portion 244 and the third bag-like structure portion 246 are joined at end points 245A and 245B, respectively.

[0091] Therefore, when the fluid (air) is discharged from the second bag-like structure portion 244 and the fluid (air) is supplied to the third bag-like structure portion 246, the inner length of the third bag-like structure portion 246 is constrained by the length of the second bag-like structure portion 244 through the endpoints 245A and 245B connected to the second bag-like structure portion 244. In contrast, the outer endpoints 247A and 247B are not constrained and thus extend to the original length of the third bag-like structure portion 246.

[0092] As a result, the length of the inner side and the outer side of the third bag-shaped structure 246 differs, and the third bag-shaped structure 246 is deformed in a manner of bending toward the inner side. Figure 4 As shown, the flexible belt 210 (receiving coil 203 ) is wound around the examination site of the subject 102 .

[0093] On the other hand, when air is discharged from the third bag-like structure portion 246 and air is supplied to the second bag-like structure portion 244, the inner length of the second bag-like structure portion 244 is constrained by the length of the first bag-like structure portion 242 through the endpoints 243A and 243B connected to the first bag-like structure portion 242. In contrast, the outer endpoints 245A and 245B are not constrained and thus extend to the original length of the second bag-like structure portion 244.

[0094] As a result, the second bag-like structure 244 stretches, and the flexible belt 240 is stretched as a whole. However, in this example, the second bag-like structure 244 is constrained by the length of the first bag-like structure 242 through the end points 243A and 243B connected to the first bag-like structure 242, so there is a difference between the length of the inside and the outside of the second bag-like structure 244, and the second bag-like structure 244 is deformed in a manner of bending inward. However, it is preferred to design the difference in length between the first bag-like structure 242 and the second bag-like structure 244, or to adjust the air pressure supplied to the second bag-like structure 244, so that the first bag-like structure 242 having the receiving coil 203 does not fit closely to the examination site of the subject 102 (preferably, the subject 102 is not restrained by the flexible belt 240).

[0095] Furthermore, since the first bag-like structure portion 242 is joined to the end points 243A and 243B of the second bag-like structure portion 244 , respectively, the first bag-like structure portion 242 expands as the second bag-like structure portion 244 expands.

[0096] As described above, by extending the second bag-like structure 244 in a curved shape, the first bag-like structure 242 accommodating the receiving coil 203 can also be extended in a curved shape, so that the receiving coil 203 can be prepared for winding around the examination site and can be unwound.

[0097] Figure 6 This is a conversion diagram showing the outline of the action of the flexible belt accommodating the receiving coil and the movement of the bed.

[0098] Figure 6 (A) shows the state where the subject 102 is sitting on the upper plate 132 of the bed before the examination. Figure 4 The air supply to the flexible belt 240 is shown in FIG. 1. Also, the upper plate 132 is located at the descending end.

[0099] Then, if Figure 6 As shown in (B), the subject 102 lies supinely on the upper plate 132. The operator preferably adjusts the position of the subject 102 lying supinely on the upper plate 132. This is to allow the flexible belt 240 to be accurately wound around the examination site of the subject 102.

[0100] Then, the operator operates the operation unit described later to instruct the flexible belt 240 (receiving coil 203) to be wound around the examination area of ​​the subject 102. When the instruction to wind the receiving coil 203 is given, first, air is supplied to the second bag-like structure 244 of the flexible belt 240, thereby the flexible belt 240, which has shrunk as a whole, is bent and expanded ( Figure 6 (B)).

[0101] Then, if Figure 6As shown in (C), the upper plate 132 rises to a height that allows entry and exit of the cavity of the gantry 110 of the MRI apparatus. Air is supplied to the third bag-shaped structure 246 of the flexible belt 240 and air is exhausted from the second bag-shaped structure 244, so that the flexible belt 240 is automatically wound around the examination area of ​​the subject 102. Figure 6 In the example shown, the examination part of the subject 102 is the head. In addition, the flexible belt 240 may be automatically wound around the examination part of the subject 102 by supplying air to the third bag-like structure part 246 instead of exhausting air from the second bag-like structure part 244. At this time, it is preferable to appropriately adjust the air pressure supplied to the second bag-like structure part 244 and the air pressure supplied to the third bag-like structure part 246.

[0102] Then, if Figure 6 As shown in (D), the upper plate 132 is inserted into the cavity of the gantry 110 of the MRI apparatus. In this way, an MRI examination of the examination site of the subject 102 can be performed. Figure 6 (B) and Figure 6 The bed (C) and the winding control of the flexible belt 240 can also be performed simultaneously.

[0103] Then, when the examination is finished, the control of the bed and the control of the flexible belt 240 are performed in the reverse order to the above.

[0104] Figure 7 Yes means Figure 4 1 and 2, which are diagrams showing an example of a driving and controlling unit for a flexible belt, the receiving coil device according to the second embodiment includes a flexible belt 240, a fluid pressure circuit 250, a control unit 260, and an operating unit 232.

[0105] exist Figure 7 In the embodiment, a portion of the outer side of the third bag-shaped structure 246 of the flexible belt 240 is fixed to the bed 130 (upper plate 132 ) by a fixing portion 240A. The fixing portion 240A may be set to a structure that is detachable from the upper plate 132 .

[0106] The fluid pressure circuit 250 is composed of an air compressor 251 , a first hose 252 , a second hose 254 , a solenoid valve 256 , a pressure sensor 226 , and a pressure reducing valve 228 .

[0107] One end of the first hose 252 and the second hose 254 are connected to the air supply and exhaust ports of the second bag-like structure 244 and the third bag-like structure 246 , respectively, and the other end is connected to the air compressor 251 or the exhaust port via the solenoid valve 256 .

[0108] The solenoid valve 256 is a three-position four-way solenoid valve disposed on the first hose 252 and the second hose 254 .

[0109] When the solenoid 256A is energized, the solenoid valve 256 can supply compressed air from the air compressor 251 to the third bag-like structure 246 via the solenoid valve 256 and the second hose 254 , and can discharge air from the second bag-like structure 244 to the atmosphere via the first hose 252 and the solenoid valve 256 .

[0110] When the solenoid 256B is energized, the solenoid valve 256 can supply compressed air from the air compressor 251 to the second bag-like structure 244 via the solenoid valve 256 and the first hose 252 , and can discharge air from the third bag-like structure 246 to the atmosphere via the second hose 254 and the solenoid valve 256 .

[0111] The pressure sensor 226 detects the pressure of air supplied from the air compressor 251 to the second bag-like structure portion 244 or the third bag-like structure portion 246 , and outputs a pressure signal indicating the detected air pressure to the control unit 260 .

[0112] The pressure reducing valve 228 opens when the pressure of the air supplied to the second bag-like structure portion 244 or the third bag-like structure portion 246 reaches an abnormal pressure, and functions as a safety valve for exhausting the air.

[0113] The control unit 260 controls the air compressor 251 and the electromagnetic valve 256 according to an instruction to wind the receiving coil 203 or an instruction to unwind the receiving coil 203 from the operation unit 232, and winds the flexible belt 240 (receiving coil 203) around the examination area of ​​the subject 102 or unwinds the receiving coil 203 around the examination area.

[0114] That is, when the control unit 260 receives a winding instruction for the receiving coil 203 from the operating unit 232 , it excites the solenoid 256A of the electromagnetic valve 256 , and then drives the air compressor 251 to drive the control pressure increase / decrease pump 221 so that compressed air is ejected from the air compressor 251 .

[0115] Thus, the compressed air discharged from the air compressor 251 is supplied to the third bag-like structure 246 via the solenoid valve 256 and the second hose 254 , and the air in the second bag-like structure 244 is discharged via the first hose 252 and the solenoid valve 256 .

[0116] Then, when the control unit 260 detects that the pressure in the third bag-shaped structure part 246 of the flexible belt 240 reaches a preset reference pressure based on the detection signal of the pressure sensor 226, the air compressor 251 is stopped, and then the solenoid 256A of the electromagnetic valve 256 is demagnetized to return the spool of the electromagnetic valve 256 to the position where the pressure in the third bag-shaped structure part 246 of the flexible belt 240 reaches a preset reference pressure. Figure 7 Position shown.

[0117] As described above, by supplying compressed air to the third bag-like structure 246, a difference is generated in the length of the outer circumference and the inner circumference of the third bag-like structure 246. Figure 4 The flexible belt 240 (receiving coil 203) is bent inwardly as shown, and is wound around the subject 102. In addition, the length of the inner circumference of the third bag-like structure 246 is restricted by the length of the second bag-like structure 244, so when compressed air is supplied to the third bag-like structure 246, the length of the outer circumference and the inner circumference of the third bag-like structure 246 will differ.

[0118] On the other hand, when the control unit 260 receives an instruction to unwind the receiving coil 203 from the operating unit 232, it energizes the solenoid 256B of the electromagnetic valve 256 and then drives the air compressor 251 to drive the control pressure increase / decrease pump 221 so that compressed air is ejected from the air compressor 251.

[0119] Thus, the compressed air discharged from the air compressor 251 is supplied to the second bag-like structure 244 via the solenoid valve 256 and the first hose 252 , and the air in the third bag-like structure 246 is discharged via the second hose 254 and the solenoid valve 256 .

[0120] Then, when the control unit 260 detects that the pressure in the second bag-like structure portion 244 of the flexible belt 240 reaches the reference pressure based on the detection signal of the pressure sensor 226, the air compressor 251 is stopped, and then the solenoid 256A of the electromagnetic valve 256 is demagnetized to return the spool of the electromagnetic valve 256 to the reference pressure. Figure 7 Position shown.

[0121] The inner end points 243A and 243B of the second bag-shaped structure 244 are constrained by the first bag-shaped structure 242, while the inner end points 243A and 243B of the second bag-shaped structure 244 are not constrained by the third bag-shaped structure 246. Therefore, the inner and outer lengths of the second bag-shaped structure 244 differ, and the second bag-shaped structure 244 is deformed to bend inward. However, the second bag-shaped structure 244 is bent and stretched (expanded) without constraining the inspection site, so the winding of the receiving coil 203 around the inspection site is released.

[0122] In addition, Figure 7 The signal cable for acquiring NMR signals from the receiving coil 203 is omitted, but the signal cable, the first hose 252, and the second hose 254 are wired and piped in a manner that does not hinder the movement of the upper plate 132 of the bed. Figure 7In the fluid pressure circuit 250 shown, an accumulator is provided on the discharge port side of the air compressor 251 , and the air compressor 251 is driven when the compressed air accumulated in the accumulator becomes equal to or lower than a reference pressure.

[0123] [Other embodiments]

[0124] Figure 3 and Figure 7 The control unit 230 and the control unit 260 shown in the figure control the fluid pressure circuits 220 and 250 respectively according to the winding instruction of the receiving coil 203 or the winding unwinding instruction of the receiving coil 203 from the operation unit 232 operated by the operator, so that the receiving coil 203 is wound around the subject and the unwinding is performed, but it is not limited to this. The fluid pressure circuits 220 and 250 can also be controlled by using the instruction to move the bed 130 or the specified time point of the bed movement as a trigger point.

[0125] For example, Figure 2 When the control unit 140 shown receives an instruction to raise the bed 130 from the operating unit 150 and controls the bed 130 to rise, the control units 230 and 260 can receive the instruction to raise the bed 130 as a winding instruction for the receiving coil and control the fluid pressure circuits 220 and 250, or can receive the first time point in the control of the rise of the bed 130 (for example, the time point when the rise of the bed 130 ends) as a winding instruction for the receiving coil and control the fluid pressure circuits 220 and 250.

[0126] Likewise, Figure 2 When the control unit 140 shown receives an instruction from the operation unit 150 to pull out the bed 130 (upper plate 132) from the cavity 120 of the gantry 110 of the MRI apparatus 100 and performs control to pull out the upper plate 132 from the cavity 120, the control units 230 and 260 may receive the instruction to pull out the bed 130 as an instruction to unwind the receiving coil and control the fluid pressure circuits 220 and 250, or may receive a second time point in the control of pulling out the bed 130 (for example, a time point when the upper plate 132 of the bed 130 is completely pulled out from the gantry 110) as an instruction to unwind the receiving coil and control the fluid pressure circuits 220 and 250.

[0127] This eliminates the need for the operator to issue an instruction to wind the receiving coil or to unwind the receiving coil through the operation unit, and thus the burden on the operator can be further reduced.

[0128] In addition, if Figure 4 and Figure 5As shown, the flexible belt 240 of the second embodiment has a first bag-like structure portion 242 as the innermost first layer, a second bag-like structure portion 244 for stretching the flexible belt 240 is provided on the outer peripheral side of the first bag-like structure portion 242 as the second layer, and a third bag-like structure portion 246 for bending the flexible belt 240 is provided on the outer peripheral side of the second bag-like structure portion 244 as the third layer, but is not limited to this, and a third bag-like structure portion 246 may also be provided between the first bag-like structure portion 242 and the second bag-like structure portion 244.

[0129] That is, the first bag-like structure 242 of the first layer may be arranged on the innermost side of the flexible belt 240, the order of the second bag-like structure 244 and the third bag-like structure 246 arranged on the outer peripheral side of the first bag-like structure 242 may be reversed, and the third layer and the second layer may be overlapped and joined in sequence on the outer peripheral side of the first bag-like structure 242 (first layer). In this case, the length of the first bag-like structure 242 of the first layer is set to be shorter than the lengths of the second bag-like structure 244 and the third bag-like structure 246, and the length of the second bag-like structure 244 is set to be the same as the length of the third bag-like structure 246, and the end points of both ends of each bag-like structure are respectively as follows: Figure 5 Just fix it as shown.

[0130] Furthermore, since the receiving coil 203 is accommodated in the first bag-shaped structure portion 242 on the innermost peripheral side, the receiving coil 203 can be brought close to the examination site of the subject 102 when the flexible belt 240 is bent.

[0131] [other]

[0132] In this embodiment, one flexible belt containing a receiving coil used for head examination is set on the bed, but two or more flexible belts used for examination of other examination parts of the subject (chest, abdomen, joints of hands and feet, etc.) may be set on the bed, or it may be set so that a desired flexible belt can be installed on the bed. In this case, the fluid pressure circuit and control unit for driving the flexible belt can be shared by each flexible belt.

[0133] Furthermore, in the present embodiment, a case where gas such as air is supplied as the fluid supplied to the flexible belt is described, but the present invention is not limited thereto, and liquid such as water may be supplied, and the type of fluid is not limited.

[0134] Furthermore, the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention.

Claims

1. A receiving coil device, which is arranged in a magnetic resonance imaging device and receives nuclear magnetic resonance signals, the receiving coil device comprising: A receiving coil, receiving the nuclear magnetic resonance signal; and A flexible belt accommodates the receiving coil and is partially fixed on the bed. The flexible belt changes shape by supplying and / or discharging fluid and winds the receiving coil around the examination site of the subject on the bed or unwinds the receiving coil.

2. The receiving coil device according to claim 1, wherein: The flexible belt is formed by bonding a first layer and a second layer, the first layer accommodating the receiving coil, and the second layer having a bag-like structure portion and being bent or stretched by the fluid supplied to or discharged from the bag-like structure portion, The flexible belt bends to wrap the receiving coil around the inspection site when the fluid is supplied to the bag-like structure, and unwraps the receiving coil when the fluid is discharged from the bag-like structure.

3. The receiving coil device according to claim 2, wherein: The first layer has a first pocket-shaped structure portion that accommodates the receiving coil.

4. The receiving coil device according to claim 2, wherein: The first layer is arranged on the inner peripheral side of the curved flexible belt.

5. The receiving coil device according to claim 1, wherein: The flexible belt is composed of a first layer, a second layer, and a third layer joined together, the first layer accommodating the receiving coil, the second layer having a second bag-shaped structure portion and being stretched by the fluid supplied to the second bag-shaped structure portion, and the third layer having a third bag-shaped structure portion and being bent by the fluid supplied to the third bag-shaped structure portion, The flexible belt stretches the receiving coil to at least release the winding around the inspection part when the fluid is discharged from the third bag-like structure and supplied to the second bag-like structure, and bends to wind the receiving coil around the inspection part when the fluid is supplied to the third bag-like structure.

6. The receiving coil device according to claim 5, wherein: The flexible belt overlaps and joins the first layer, the second layer, and the third layer in order from the innermost circumference of the flexible belt, or overlaps and joins the second layer, the first layer, and the third layer in order from the innermost circumference of the flexible belt.

7. The receiving coil device according to claim 5, wherein: The first layer is arranged on the innermost peripheral side of the curved flexible belt, and the second layer and the third layer are arranged on the outer peripheral side of the first layer.

8. The receiving coil device according to claim 5, wherein: The first layer has a first pocket-shaped structure portion that accommodates the receiving coil.

9. The receiving coil device according to claim 2, comprising: a fluid pressure circuit having a fluid pressure source for supplying and / or discharging the fluid, a hose disposed between the fluid pressure source and the bag-like structure, and a solenoid valve disposed in the hose for switching the direction of the fluid flowing through the hose; and A control unit controls the fluid pressure source and the solenoid valve, When receiving a winding instruction for the receiving coil, the control unit controls the fluid pressure source and the solenoid valve so that the fluid is supplied from the fluid pressure source to the bag-like structure via the solenoid valve and the hose to wind the receiving coil around the inspection site. When receiving a winding release instruction for the receiving coil, the control unit discharges the fluid from the bag-like structure via the hose and the solenoid valve to release the winding of the receiving coil around the inspection site.

10. The receiving coil device according to claim 5, comprising: a fluid pressure circuit having a fluid pressure source for supplying and / or discharging the fluid, a first hose and a second hose disposed between the fluid pressure source and the second bag-like structure and the third bag-like structure, and a solenoid valve disposed in the first hose and the second hose to switch the direction of the fluid flowing through the first hose and the second hose; and A control unit controls the fluid pressure source and the solenoid valve, When receiving a winding instruction for the receiving coil, the control unit controls the fluid pressure source and the solenoid valve so that the fluid is discharged from the second bag-like structure portion via the first hose and the solenoid valve, and the fluid is supplied from the fluid pressure source to the third bag-like structure portion via the solenoid valve and the second hose to wind the receiving coil around the inspection portion. When receiving a winding release instruction for the receiving coil, the fluid is discharged from the third bag-like structure portion via the second hose and the solenoid valve, and the fluid is supplied from the fluid pressure source to the second bag-like structure portion via the solenoid valve and the first hose to release the winding of the receiving coil around the inspection portion.

11. The receiving coil device according to claim 9, wherein: The control unit receives an instruction to raise the bed or a first time point during the raising control of the bed as a winding instruction for the receiving coil.

12. The receiving coil device according to claim 9, wherein: The control unit receives an instruction to pull out the bed from the gantry of the magnetic resonance imaging apparatus or a second time point during the control of pulling out the bed as an instruction to unwind the receiving coil. 13 . A magnetic resonance imaging apparatus comprising the receiving coil device according to claim 1 .

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