Radio frequency coil system and magnetic resonance imaging equipment

Abstract

The invention provides a radio frequency coil system applied to magnetic resonance imaging equipment. The radio frequency coil system comprises a cylinder; the radio frequency coil is arranged on the cylinder body in a surrounding manner, the radio frequency coil is arranged on the cylinder body in a surrounding manner, and the radio frequency coil comprises a plurality of crosspiece parts and two end parts; each crosspiece part extends along the axial direction of the radio frequency coil; each end part comprises a plurality of end part subunits, and the plurality of end part subunits are arranged along the circumferential direction of the radio frequency coil; every two adjacent crosspiece parts and the multiple end part subunits located between the two crosspiece parts form a loop; the radio frequency coil comprises a plurality of loops, each loop is correspondingly connected with one power line, and the power lines are used for transmitting driving signals. Compared with the prior art, each power line independently transmits the driving signal to the corresponding loop, so that the radio frequency field generated by the radio frequency coil is distributed more uniformly, and the magnetic resonance imaging effect is better.

Description

[0001] Description of the case

[0002] This application is a divisional application filed for the Chinese application with application date of May 10, 2021, application number 202110505951.4, and invention name “Radio Frequency Coil System and Magnetic Resonance Imaging Equipment”. Technical Field

[0003] The present invention relates to the technical field of medical devices, and in particular to a radio frequency coil system and a magnetic resonance imaging device. Background Art

[0004] like Figure 1 As shown, Figure 1 It is a radio frequency coil system of the prior art, comprising a cylinder 01, a body radio frequency coil 02 arranged around the cylinder, and a feeding port 03 and a power supply port 04 provided on the cylinder. The feeding port 03 generates a radio frequency signal and transmits it to the body radio frequency coil, and the power supply port 04 generates a DC signal and transmits it to the body radio frequency coil. In the prior art, two feeding ports 03 are provided on the cylinder, and the two feeding ports are usually symmetrical about the central axis of the cylinder 02 along the radial direction of the cylinder 02. The radio frequency fields generated by the two feeding ports 03 are relatively unevenly distributed; the two power lines of the two feeding ports 03 are connected to the nearest line and are not brought together for unified grounding, which can easily cause phase deviation of the radio frequency signal, and at the same time, the common mode signal is not effectively suppressed; the power line of the feeding port 03 and the power supply line of the power supply port are both connected to the same end along the axial direction of the cylinder 02 ( Figure 1 In the example, both wires exit at the left end of the cylinder). Although this has advantages from the perspective of magnetic resonance services, there is a risk of interference between RF and DC signals. Summary of the Invention

[0005] The object of the present invention is to provide a radio frequency coil system and a magnetic resonance imaging device to solve the problem of uneven radio frequency field generated by the existing radio frequency coil system.

[0006] To solve the above technical problems, according to one aspect of the present invention, the present invention provides a radio frequency coil system, comprising:

[0007] Cylinder;

[0008] a radio frequency coil, which is arranged around the cylindrical body, and includes a plurality of feeding ports arranged at intervals along the circumference of the radio frequency coil;

[0009] A plurality of feeding components are arranged on the cylindrical body, the feeding components correspond to the feeding ports one by one, and the feeding components are connected to the corresponding feeding ports.

[0010] Optionally, the plurality of feeding assemblies are arranged at intervals along the circumference of the cylinder body, and at least some of the feeding assemblies are arranged in a circumferential direction.

[0011] Optionally, the feeding assembly comprises a power line and a wave limiter, one end of the power line is connected to the feeding port to transmit a driving signal, and the wave limiter is used to limit the transmission of the driving signal of a preset frequency to the radio frequency coil.

[0012] Optionally, the power line has a power supply end led out from the end connected to the feeding port, and the power supply ends of at least two feeding assemblies converge to form a wire harness group, and the wire harness group is fixed to a preset position of one end of the cylinder body in the axial direction.

[0013] Optionally, the power supply ends of all the feeding assemblies converge to form one wire harness group.

[0014] Optionally, the radio frequency coil system further comprises a power supply assembly, the power supply assembly comprises a power supply line connected to the radio frequency coil, the feeding assembly comprises a power line connected to the radio frequency coil, and the power line and the power supply line are distributed on both sides of the cylinder body in the axial direction thereof.

[0015] Optionally, the radio frequency coil system further comprises a plurality of tuning assemblies and a plurality of coupling assemblies arranged at intervals along the circumference of the cylinder body, the adjustment ends of the plurality of tuning assemblies are located on one side of the cylinder body in the axial direction, and the adjustment ends of the plurality of coupling assemblies are located on one side of the cylinder body in the axial direction.

[0016] Optionally, the tuning assembly comprises a tuning rod and a tuning capacitor, and the coupling assembly comprises a coupling rod and a coupling capacitor.

[0017] Optionally, the cylinder body has a plurality of grooves recessed inwardly along the radial direction of the cylinder body, at least a first part of the grooves are used to accommodate the tuning capacitors, and at least a second part of the grooves are used to accommodate the coupling capacitors.

[0018] Based on another aspect of the present application, the present application further provides a magnetic resonance imaging device comprising the radio frequency coil system as described above.

[0019] To sum up, in the radio frequency coil system and the magnetic resonance imaging device provided by the application, the radio frequency coil system comprises a barrel, a radio frequency coil arranged around the barrel, the radio frequency coil comprising a plurality of feed ports arranged along the circumferential direction of the radio frequency coil, and a plurality of feed assemblies arranged on the barrel, the feed assemblies corresponding to the feed ports one by one, and the feed assemblies being connected with the corresponding feed ports to transmit driving signals to the radio frequency coil. Compared with the prior art, the radio frequency field distribution generated by the radio frequency coil is more uniform by arranging a plurality of feed ports and a plurality of corresponding feed assemblies, so that the effect of magnetic resonance imaging is better. BRIEF DESCRIPTION OF DRAWINGS

[0020] Those skilled in the art should understand that the provided drawings are used to better understand the application, and do not constitute any limitation on the scope of the application. Among them:

[0021] Figure 1 is a schematic diagram of a radio frequency coil system of the prior art;

[0022] Figure 2 and Figure 3 is a schematic diagram of a radio frequency coil system of an embodiment of the application;

[0023] Figure 4 is a schematic diagram of a radio frequency coil of an embodiment of the application;

[0024] Figure 5 is Figure 4 is an equivalent diagram of the radio frequency coil in

[0025] Figure 6 is an equivalent diagram of a loop of the radio frequency coil of an embodiment of the application;

[0026] Figure 7 and Figure 8 is Figure 3 is an enlarged view of part A in

[0027] Figure 9 is a schematic diagram of a barrel of an embodiment of the application;

[0028] Figure 10 is Figure 3 is an enlarged view of part B in

[0029] Figure 11 is a schematic diagram of a switch unit of an embodiment of the application.

[0030] In the drawings:

[0031] 01-barrel; 02-radio frequency coil; 03-feed port; 04-power supply port;

[0032] 10 - barrel; 11 - first wire channel; 110 - preset position; 12 - second wire channel; 13 - groove;

[0033] 20 - radio frequency coil; 200 - feed port; 21 - crosspiece portion; 210 - crosspiece subunit; 22 - end portion; 220 - end portion subunit; LOOP - loop;

[0034] 30 - feed assembly; 31 - power line; 310 - wire harness group; 32 - wave limiter; 41 - power supply line; 50 - tuning assembly; 51 - tuning rod; 52 - tuning capacitor; 53 - tuning sleeve; 54 - tuning coupling capacitor; 60 - preset fixed capacitor. DETAILED DESCRIPTION

[0035] To make the objects, advantages and features of the present application more clearly, the following further describes the present application in conjunction with the drawings and specific embodiments. It should be noted that the drawings are very simplified and not drawn in proportion, and are only used to facilitate and clearly assist the purpose of describing the embodiments of the present application. In addition, the structures shown in the drawings are often a part of the actual structures. In particular, the emphasis of each drawing needs to be different, and sometimes different proportions are used.

[0036] As used in the present application, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. The term "or" is generally employed in its sense of "and / or" unless the content clearly dictates otherwise. The term "at least two" is generally employed in its sense of "two or more" unless the content clearly dictates otherwise. In addition, the terms "first," "second," "third," are used only for the purpose of description and should not be construed as indicating or implying relative importance or implying the number of the technical features indicated. Therefore, the features defined as "first," "second," "third" can explicitly or implicitly include one or at least two of the features, unless the content clearly indicates otherwise.

[0037] The present application provides a radio frequency coil system and a magnetic resonance imaging device to solve the problem of non-uniform radio frequency field generated by the existing radio frequency coil system.

[0038] The following description is made with reference to the accompanying drawings.

[0039] As shown in Figure 2 and Figure 3 , Figure 2 and Figure 3is a schematic diagram of a radio frequency coil system according to an embodiment of the present application, the embodiment provides a radio frequency coil system, which comprises: a cylinder 10; a radio frequency coil 20, which is arranged around the cylinder 10, the radio frequency coil 20 comprises a plurality of feed ports 200 arranged along the circumferential direction of the radio frequency coil 20; a plurality of feed assemblies 30, which are arranged on the cylinder 10, the feed assemblies 30 correspond to the feed ports 200 one by one, and the feed assemblies 30 are connected with the corresponding feed ports 200 to transmit a driving signal (such as a radio frequency driving signal) to the radio frequency coil 20. In the embodiment, the shape of the cylinder 10 is substantially annular cylindrical, and the scanning cavity of the cylinder 10 is used to load a subject to be examined and complete scanning imaging under a related instrument of magnetic resonance imaging.

[0040] Optionally, the radio frequency coil system can be connected with a control system, which can comprise a FPGA (Field-Programmable Gate Array) control unit, a DAC (Digital to analog converter) unit, a radio frequency amplifier and a power divider connected in sequence, wherein the radio frequency sequence transmitted by the FPGA control unit is converted into an analog signal by the DAC unit, amplified by the radio frequency amplifier, and then converted into a driving signal by the power divider, and sent to the plurality of feed ports 200 of the radio frequency coil 20, so as to drive the radio frequency coil 20 to generate a circularly polarized field.

[0041] The radio frequency coil 20 is a key component of an MRI device, and the radio frequency coil 20 can have a transmitting function, or simultaneously have a transmitting function and a receiving function. The radio frequency coil 20 in the embodiment simultaneously has a transmitting function and a receiving function, specifically, when the radio frequency coil 20 is in a transmitting state controlled by a switch, a radio frequency pulse is transmitted to the subject to be examined to generate a radio frequency field, so that some atoms containing single protons (such as hydrogen atoms) in the body of the subject to be examined absorb energy to produce resonance; when the radio frequency coil 20 is in a receiving state controlled by a switch, the MR signal (similar to a kind of radio wave) formed by the resonance of the atoms in the body of the subject to be examined is received.

[0042] Further, the radio frequency coil 20 in the embodiment can be a volume coil, and further can be a degenerate birdcage coil. As described above, through the arrangement of the plurality of feed ports 200 arranged along the circumferential direction of the radio frequency coil 20 and the corresponding plurality of feed assemblies 30, when the radio frequency coil 20 is in a transmitting state, the radio frequency field generated by the radio frequency coil 20 is more uniform than that of the radio frequency coil 20 in the prior art, so that the clarity of magnetic resonance imaging is better, and the imaging quality is higher, which is further conducive to the judgment of the pathological cause of the subject to be examined by the operator.

[0043] Further, as shown in Figure 4 and Figure 5 , the radio frequency coil system can further comprise a radio frequency coil 20, which is arranged around the cylinder 10, and the radio frequency coil 20 comprises a plurality of feed ports 200 arranged along the circumferential direction of the radio frequency coil 20; a plurality of feed assemblies 30, which are arranged on the cylinder 10, the feed assemblies 30 correspond to the feed ports 200 one by one, and the feed assemblies 30 are connected with the corresponding feed ports 200 to transmit a driving signal (such as a radio frequency driving signal) to the radio frequency coil 20. Figure 4is a schematic view of a radio frequency coil of an embodiment of the present application, Figure 5 is Figure 4 is an equivalent diagram of the radio frequency coil in , the radio frequency coil 20 comprises a plurality of crosspiece parts 21 and two end parts 22, the crosspiece part 21 is provided with a cross-end antenna, the end part 22 is provided with an end ring antenna, the end part 22 is arranged at the two ends of the crosspiece part 21 and the two end positions between adjacent two crosspiece parts 21, and the crosspiece part 21 is connected with the end part 22 at its two ends respectively, the plurality of crosspiece parts 21 are arranged along the circumferential direction of the radio frequency coil 20 (preferably uniformly spaced), and the crosspiece part 21 extends along the axial direction of the radio frequency coil 20. Among them, the crosspiece part 21 comprises a plurality of crosspiece sub-units 210 arranged in sequence along the axial direction of the radio frequency coil 20, the adjacent two crosspiece sub-units 210 are connected by a capacitor, generally, the two adjacent crosspiece sub-units 210 located at the middle position of the crosspiece part 21 are connected by a fixed capacitor, and the two crosspiece sub-units 210 on the crosspiece part 21 close to the end part 22, or the crosspiece sub-units 210 on the crosspiece part 21 for connecting with the end part 22, are connected by an adjustable capacitor (i.e. the capacitance value of the capacitor can be adjusted). In this way, the error of each fixed capacitor can be adjusted by the adjustable capacitor, so as to realize accurate transmission frequency calibration. In addition, each end part 22 comprises a plurality of end part sub-units 220, and the plurality of end part sub-units 220 are arranged along the circumferential direction of the radio frequency coil 20, so as to form a ring-shaped end part 22.

[0044] In the embodiment, the adjacent two crosspiece parts 21 together with the plurality of end part sub-units 220 located between the two crosspiece parts 21 form a loop LOOP, so it can be known that the radio frequency coil 20 comprises a plurality of loops LOOP arranged along the circumferential direction, and the number of the loops LOOP is equal to the number of the crosspiece parts 21 of the radio frequency coil 20, and it can be further known that the number of the feed ports 200 of the embodiment is equal to the number of the loops LOOP, that is, one feed port 200 acts on one loop LOOP, and optionally, the position of the feed port 200 can be arranged on the end part 22, such as in the embodiment (see Figure 5 ), a plurality of feed ports 200 are arranged on the same end part 22 along the circumferential direction of the radio frequency coil 20, that is, the feed port 200 is located on the end part sub-unit 220.

[0045] Further, the adjacent two crosspiece sub-units 210 can be connected by a fixed capacitor or an adjustable capacitor, the embodiment considers that the position accuracy of each loop LOOP is not the same when the radio frequency coil 20 is installed on the cylinder body 10, and the fixed capacitor connected between the crosspiece sub-units 210 has a deviation, and the embodiment preferably arranges that the adjacent two crosspiece sub-units 210 are connected by an adjustable capacitor, so as to realize the adjustment of the resonant frequency of different loops LOOP, thereby realizing the accurate resonant frequency adjustment of the radio frequency coil 20.

[0046] Further, please refer to Figure 6 , Figure 6 is an equivalent diagram of the loop LOOP of the radio frequency coil 20 in an embodiment of the present application, Figure 6 The current flow direction of one of the loops LOOP is exemplarily marked in the figure. It should be noted that the current flow directions of the loops LOOP can be the same as each other or different from each other, depending on the amplitudes and phases of the power currents supplied to each loop LOOP, which can be configured according to actual conditions by those skilled in the art, and the embodiment will not be described in detail.

[0047] In one embodiment, the current flowing through the loops LOOP of the radio frequency coil 20 is distributed in a discrete form, and the current corresponding to the nth loop LOOP is approximately:

[0048]

[0049] wherein J leg (n) is the current on the nth loop LOOP; and N is the total number of the loops LOOP. For example, when N is 12, the first loop LOOP to the twelfth loop LOOP is counted clockwise. The currents on the first loop LOOP and the sixth loop LOOP are the largest. Correspondingly, different current source signals can be provided for different loops LOOP. Of course, it can be understood that each feeding component 30 can be connected to a different power amplifier, and the amplitudes and phases of the driving signals generated by each power amplifier can also be independently set, i.e., the amplitudes and phases of the driving signals of each loop LOOP can be independently set.

[0050] Based on the above principle, the radio frequency coil system of the present embodiment further comprises a plurality of tuning components 50 and a plurality of coupling components 50 arranged along the circumference of the cylinder 10; the tuning components 50 are used to adjust the resonant frequency of the radio frequency coil 20, to achieve accurate correction of the transmission frequency, and the adjustment ends of the plurality of tuning components 50 are located on one side of the cylinder 10 along the axial direction; the coupling components are used to adjust the loop LOOP coupling of the radio frequency coil 20, that is, to adjust the coupling degree between adjacent loops LOOP; the adjustment ends of the plurality of coupling components are located on one side of the cylinder 10 along the axial direction. Here, the adjustment end of the tuning component refers to the part of the tuning component used for tuning by the operator; the adjustment end of the coupling component refers to the part of the coupling component used for coupling (adjusting the coupling between the loops LOOP) by the operator. The adjustment ends of the plurality of tuning components 50 are located on one side of the cylinder 10 along the axial direction, and the adjustment ends of the plurality of coupling components are located on one side of the cylinder 10 along the axial direction, including two cases: (1) the adjustment ends of the plurality of tuning components 50 are located on one side of the cylinder 10 along the axial direction, and the adjustment ends of the plurality of coupling components are located on the other side of the cylinder 10 along the axial direction, such as the adjustment ends of the tuning components 50 on the left side and the adjustment ends of the coupling components on the right side; (2) the adjustment ends of the plurality of tuning components 50 and the adjustment ends of the plurality of coupling components are located on one side of the cylinder 10 along the axial direction, such as both on the left side or the right side of the cylinder 10. In this way, it is convenient for the operator to uniformly tune and / or couple on one side of the cylinder 10, which is more convenient and fast to implement.

[0051] Considering that there is a certain error for each fixed capacitor, the error of the fixed capacitor can be adjusted through the tuning component 50 to achieve accurate transmission frequency calibration. Further, please refer to Figure 7 and Figure 8 , Figure 7 and Figure 8 are Figure 3 , the tuning component 5050 comprises a tuning rod 51 and a tuning capacitor 52, the tuning capacitor 52 is arranged on the radio frequency coil 20, and the tuning capacitors 52 of the plurality of tuning components 50 are located on the same side along the axial direction of the cylinder 10; the tuning rod 51 extends along the axial direction of the cylinder 10 and is rotatably connected with the tuning capacitor 52, and the tuning rod 51 is used to rotate around its axial direction to adjust the capacitance value of the tuning capacitor 52. Please refer to Figure 7 , for the tuning capacitor 52 arranged in the crosspiece part 21, after the tuning rod 51 is rotated, the relative distance or facing area of the metal sheets inside the tuning capacitor 52 is changed, so that the resistance value of the tuning capacitor 52 is changed, and then the resonant frequency of the radio frequency coil is adjusted.

[0052] Please refer to Figure 8The tuning capacitors 52 are arranged on the crosspieces 21 and are used to connect two adjacent crosspiece sub-units 210 near the end portions 22, or to connect an end portion 22 and a crosspiece sub-unit 210 on the crosspiece 21 (the crosspiece sub-unit 210 on one end of the crosspiece 21, such as the leftmost crosspiece sub-unit 210). After the tuning rods are rotated, the relative distance or facing area between the metal sheets inside the tuning capacitors 52 is changed, so that the resistance value of the tuning capacitors 52 is changed, and the decoupling between adjacent loops LOOP is realized, thereby avoiding damage to the radio frequency coil 20.

[0053] The tuning assembly includes a tuning rod and a tuning capacitor, the tuning capacitor is arranged on the radio frequency coil 20, and the tuning capacitors of the plurality of tuning assemblies are located on the same side of the axial direction of the cylinder 10; the tuning rod extends along the axial direction of the cylinder 10 and is rotatably connected with the tuning capacitor, and the tuning rod is used to rotate around its axial direction to adjust the capacitance value of the tuning capacitor. Specifically, the tuning capacitor is arranged on the crosspiece 21 (which can be welded) and is used to connect two adjacent crosspiece sub-units 210 near the end portion 22 on the crosspiece 21, or to connect an end portion 22 and a crosspiece sub-unit 210 on the crosspiece 21 (the crosspiece sub-unit 210 on one end of the crosspiece 21, such as the leftmost crosspiece sub-unit 210). After the tuning rods are rotated, the relative distance or facing area between the metal sheets inside the tuning capacitors 52 is changed, so that the resistance value of the tuning capacitors 52 is changed, and the decoupling between adjacent loops LOOP is realized, thereby avoiding damage to the radio frequency coil 20.

[0054] Further, a tuning sleeve 53 can be arranged on the tuning rod 51, and a gap is left between the tuning sleeve 53 and the tuning capacitor 52 to expose part of the tuning rod 51. Actually, in the magnetic resonance device, since the radio frequency coil 20 is installed inside the gradient coil, the narrow space can only change the capacitance value of the tuning capacitor 52 by rotating the slender tuning rod 51, and generally, a flathead screwdriver can be used to rotate the exposed part of the tuning rod 51. The above-mentioned "the adjustment ends of the plurality of tuning assemblies 50 are located on the same side of the axial direction of the cylinder 10", that is, the exposed part of the tuning rod 51 of the plurality of tuning assemblies 50 is located on the same side of the cylinder 10, which is convenient for technicians to operate. Similarly, a decoupling sleeve is arranged on the decoupling rod, and the arrangement mode of the decoupling rod and the decoupling sleeve in the decoupling assembly and the rotating mode of the decoupling rod can refer to the corresponding configuration of the tuning assembly 50, which will not be described here.

[0055] For the multi-channel RF coil 20, the frequency adjustment and the coupling adjustment are very complex, and the common adjustment method is to use the adjustable capacitor as described above to simplify the design and facilitate the adjustment, that is, the tuning capacitor 52 and the coupling adjustment capacitor 54 described above. However, under the high-frequency RF field, the tuning capacitor 52 and the coupling adjustment capacitor 54 have large size and occupy a large space in the RF coil system. Figure 9 Figure 9 is a schematic view of the barrel 10 of an embodiment of the present application. Therefore, the embodiment further provides a plurality of grooves 13 on the barrel 10, which are recessed inward along the radial direction of the barrel 10. At least a first part of the grooves 13 is used to accommodate the tuning capacitor 52, and at least a second part of the grooves 13 is used to accommodate the coupling adjustment capacitor 54. In this way, the tuning capacitor 52 and the coupling adjustment capacitor 54 can be sunken in the barrel 10, simplifying the space design. Preferably, the coupling adjustment capacitor 54 and the tuning capacitor 52 have a gap with the grooves 13, that is, they are not in contact with the grooves 1323. It can be understood that the tuning capacitor 52 and the coupling adjustment capacitor 54 are suspended in the grooves 13. In this way, the risk of overheating of the inner wall of the barrel 10 caused by the heat generated by the tuning capacitor 52 and the coupling adjustment capacitor 54 under high-power operation can be reduced, avoiding negative effects on the examination object.

[0056] As a more preferred scheme of the embodiment, please continue to refer to Figure 2 and Figure 3 A plurality of the feed assembly 30 are arranged at intervals along the circumference of the barrel 10, preferably equally distributed along the circumference. At least a part of the feed assembly 30 is arranged along the circumference, preferably all the feed assembly 30 is arranged along the circumference. In this way, it is beneficial for the structure arrangement and the regular distribution of the overall device. It should be noted that whether the feed assembly 30 is arranged along the circumference or not does not affect the uniformity of the RF field.

[0057] In other embodiments, at least a part of the feed assembly 30 has a gap along the axial direction of the barrel 10, that is, at least a part of the feed assembly 30 is not arranged along the circumference, for example, one feed assembly 30 can be moved a distance to the left of the barrel 10, and another feed assembly 30 can be moved a distance to the right.

[0058] Further, the feed assembly 30 includes a power line 31 and a wave limiter 32. One end of the power line 31 is connected to the feed port 200 to transmit the driving signal, that is, connected to the end sub-unit 220 of the end portion 22 of the RF coil 20. The wave limiter 32 is used to limit the transmission of the driving signal of the preset frequency to the RF coil 20, such as limiting the transmission of the RF signal of 128MHz. In this way, the frequency of the RF signal passing through each part of the RF coil 20 is the same, and the transmission frequency of each loop LOOP is the same, which is beneficial for the uniform distribution of the RF field. In order to save space, a slot is reserved on the barrel 10 for accommodating the wave limiter 32.​

[0059] Preferably, the power lines 31 are led out power supply ends other than the end connected to the feeding port 200, and the power supply ends of at least two feeding assemblies 30 are gathered to form a wire harness group 310, which is fixed to the preset position 110 of one end of the barrel 10 along the axial direction. That is, a part of the power supply ends are gathered together and grounded before being connected to a switch unit, so as to avoid the signal phase deviation caused by the inconsistent lengths of the power lines 31, thus being beneficial to suppressing the common mode signal. Preferably, all the power supply ends are gathered to form one wire harness group 310.

[0060] Specifically, please continue to refer to Figure 9 and refer to Figure 10 , Figure 10 is an enlarged view of the B part in Figure 3 , the barrel 10 is reserved with a plurality of first wire routing grooves 11 corresponding to the plurality of feeding assemblies 30 (power lines 31), and the first wire routing grooves 11 accommodate the part of the power supply ends, which are gathered together to form the preset position 110 of the barrel 10. Figure 4 In , the preset position 110 is located at the left end of the barrel 10. It should be noted that the actual position of the preset position 110 on the barrel 10 is not specifically limited in the embodiment, as long as it can gather the power supply ends. Preferably, the preset position 110 is located at one end of the barrel 10 along the axial direction. In addition, it can be understood that the first wire routing grooves 11 can arrange the power lines 31 regularly, facilitate arrangement, and avoid the power lines 31 from being entangled and disordered.

[0061] In an exemplary embodiment, the embodiment demonstrates eight feeding assemblies 30, and the power supply ends of the eight feeding assemblies 30 are all gathered to form one wire harness group 310 and are fixed at the preset position 110 of the barrel 10. The power line 31 is connected to the feeding port 200, and in fact, one end of the power line 31 is connected to one end subunit 220 on the loop LOOP, which can be understood as one power line 31 corresponding to one loop LOOP. As shown in Figure 11 , Figure 11 is a schematic view of a switch unit of an embodiment of the present application, and the power supply ends of the eight power lines 31 are connected to a switch unit after being gathered to form one wire harness group 310, and the switch unit includes a plurality of switch devices (T / R Switch) corresponding to the power lines 31, Figure 11The numbers 1-8 are shown in the figure, number 1 corresponds to the first power line 31 in the wire harness group 310, number 2 corresponds to the second power line 31 in the wire harness group 310, and so on, and number 8 corresponds to the eighth power line 31 in the wire harness group 310. In this embodiment, the switch device can be a single-pole double-throw switch. When the power supply end is connected to the radio frequency power amplifier (RFPA) through the switch, the radio frequency coil 20 is in a transmitting state. When the power supply end is connected to the receiving channel (RX) through the switch, the radio frequency coil 20 is in a receiving state. It should be noted that only the first power line 31 corresponding to number 1 and the connection relationship between the switch device, the power amplifier (RFPA1), and the receiving channel (RX1) are shown in the figure. The connection of the power lines 31 corresponding to other numbers and the switch device can be derived accordingly, and this embodiment will not be described in detail.

[0062] In this embodiment, there can also be multiple wire harness groups 310, and the cylinder 10 is reserved with the preset positions 110 corresponding to the multiple wire harness groups 310. The number of power supply ends in each wire harness group 310 can be equal or unequal. The multiple preset positions 110 are arranged at intervals along the axial direction of the cylinder 10, and preferably, the multiple preset positions 110 are distributed at the same end of the cylinder 10 along the axial direction, which is convenient for arrangement. In an exemplary embodiment, there are two wire harness groups 310, each wire harness group 310 has four power supply ends of the feeding assembly 30, and correspondingly, the cylinder 10 has two preset positions 110. The two preset positions 110 can be arranged symmetrically about the central axis of the cylinder 10 along the radial direction of the cylinder 10, so that the two wire harness groups 310 are symmetrically distributed.

[0063] Further, the radio frequency coil system further comprises a power supply assembly, the power supply assembly comprises a power supply line 41 connected with the radio frequency coil 20, and the power supply line 41 transmits a direct-current power supply signal to the radio frequency coil 20; the feeding assembly 30 comprises a power line 31 connected with the radio frequency coil 20; and the power line 31 is distributed on both sides of the cylinder 10 along the axial direction of the cylinder 10 at an end (i.e. a power supply end) different from the end connected with the radio frequency coil 20 and the end of the power supply line 41 different from the end connected with the radio frequency coil 20. Compared with the prior art in which the power supply end and the end of the power supply line 41 different from the end connected with the radio frequency coil 20 are located on the same side, the embodiment can avoid mutual interference between the radio frequency signal and the direct-current signal. In addition, the cylinder 10 can further be provided with a second wiring groove 12 for the power supply line 41.

[0064] In an embodiment, the current flowing through the loop LOOP of the radio frequency coil 20 is in a discrete form, and the current corresponding to the nth LOOP is approximately:

[0065]

[0066] wherein, J leg (n) is the current on the nth LOOP; N is the total number of the LOOPs. For example, when N is 12, the 1st LOOP to the 12th LOOP, count clockwise. The current on the 1st LOOP and the 6th LOOP is the largest. By adjusting the corresponding power supply, the power supply line 41 can provide different current source signals.

[0067] Based on another aspect of the present application, the present application further provides a magnetic resonance imaging device comprising the radio frequency coil system as described above. It can be understood that, since the magnetic resonance imaging device comprises the radio frequency coil system as described above, the magnetic resonance imaging device has the beneficial effects brought by the radio frequency coil system, and the working principle and other structural components of the magnetic resonance imaging device will not be described any more, and those skilled in the art can learn from the prior art.

[0068] In an embodiment, the magnetic resonance imaging device comprises a control system and the radio frequency coil system, the control system can comprise a FPGA (Field-Programmable Gate Array) control unit, a DAC (Digital to analog converter) unit, a radio frequency amplifier and a power divider connected in sequence, wherein the radio frequency sequence transmitted by the FPGA control unit is converted into an analog signal by the DAC unit in sequence, amplified by the radio frequency amplifier, and then converted into a driving signal by the power divider, and sent to the plurality of feeding ports 200 of the radio frequency coil 20, so as to drive the radio frequency coil 20 to generate a circularly polarized field.

[0069] In summary, in the radio frequency coil system and the magnetic resonance imaging device provided by the present application, the radio frequency coil system comprises: a barrel; a radio frequency coil surrounding the barrel, the radio frequency coil comprising a plurality of feeding ports arranged along the circumferential direction of the radio frequency coil; and a plurality of feeding assemblies arranged on the barrel, the feeding assemblies corresponding to the feeding ports one by one, and the feeding assemblies being connected to the corresponding feeding ports to transmit driving signals to the radio frequency coil. Compared with the prior art, the radio frequency field generated by the radio frequency coil is more uniform by arranging a plurality of feeding ports and a plurality of corresponding feeding assemblies, so that the effect of magnetic resonance imaging is better.

[0070] The above description is only a description of the preferred embodiments of the present application, and does not limit the scope of the present application in any way. Any modification or modification made by a person skilled in the art based on the above disclosure is within the protection scope of the claims.

Claims

1. A radio frequency coil system, used in magnetic resonance imaging equipment, characterized in that: include: Cylinder; a radio frequency coil, which is disposed around the cylindrical body, and includes a plurality of cross sections and two end sections; Each of the crosspieces extends along the axial direction of the radio frequency coil; Each of the end portions comprises a plurality of end subunits, and the plurality of end subunits are arranged along the circumference of the radio frequency coil; Two adjacent crosspieces together with the end subunit located between the two crosspieces form a loop; The radio frequency coil includes a plurality of loops, each of which is connected to a corresponding power line, and the power line is used to transmit a driving signal.

2. The radio frequency coil system according to claim 1, wherein: The RF coil system further includes a wave limiter. One end of the power line is connected to the feeding port of the RF coil to transmit a driving signal. The wave limiter is used to limit the driving signal of a preset frequency to be transmitted to the RF coil.

3. The radio frequency coil system according to claim 2, wherein: The power line is different from the end connected to the feeding port to lead out a power supply end, and at least two of the power supply ends converge to form a wiring harness group, and the wiring harness group is fixed at a preset position at one end of the cylinder along the axial direction.

4. The radio frequency coil system according to claim 1, wherein: The RF coil system further includes a power supply assembly, which includes a power supply line connected to the RF coil; the end of the power line other than the end connected to the RF coil and the end of the power line other than the end connected to the RF coil are distributed on both sides of the cylinder along its own axis.

5. The radio frequency coil system according to claim 1, wherein: The radio frequency coil system further includes a plurality of tuning components and a plurality of coupling components spaced apart along the circumference of the cylinder; the adjustment ends of the plurality of tuning components are located on one side of the cylinder along the axial direction; and the adjustment ends of the plurality of coupling components are located on one side of the cylinder along the axial direction.

6. The radio frequency coil system according to claim 5, wherein: The tuning component includes a tuning rod and a tuning capacitor; the coupling component includes a coupling rod and a coupling capacitor.

7. The radio frequency coil system according to claim 6, wherein: The cylinder has a plurality of grooves, which are recessed inwardly along the radial direction of the cylinder. At least a first portion of the grooves is used to accommodate the tuning capacitor, and at least a second portion of the grooves is used to accommodate the coupling capacitor.

8. A magnetic resonance imaging device, characterized in that include: The control system includes a radio frequency amplifier and a power divider, wherein the radio frequency amplifier amplifies the analog signal of the radio frequency sequence, and the power divider converts the amplified analog signal into a driving signal; A radio frequency coil system includes a body transmit coil comprising a plurality of rungs and two ends; Each of the crosspieces extends along the axial direction of the radio frequency coil; Each of the end portions comprises a plurality of end subunits; Two adjacent crosspieces together with the end subunit located between the two crosspieces form a loop; The radio frequency coil includes a plurality of loops, each of which is connected to a corresponding power line, and the power line is used to transmit the driving signal.

9. The radio frequency coil system according to claim 8, wherein: The RF coil system further includes a wave limiter. One end of the power line is connected to the feeding port of the RF coil to transmit a driving signal. The wave limiter is used to limit the driving signal of a preset frequency to be transmitted to the RF coil.

10. The radio frequency coil system according to claim 9, wherein: The power line is different from the end connected to the feeding port and leads to a power supply end. A plurality of the power supply ends converge to form two wiring harness groups, and each wiring harness group has four power supply ends.

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