WO2023028785A1

WO2023028785A1 - Multi-core radio frequency receiving coil structure, multi-core radio frequency receiving apparatus, and device

Info

Publication number: WO2023028785A1
Application number: PCT/CN2021/115463
Authority: WO
Inventors: 郑海荣; 李烨; 李楠; 杜凤; 陈巧燕; 刘新
Original assignee: 深圳先进技术研究院
Priority date: 2021-08-30
Filing date: 2021-08-30
Publication date: 2023-03-09

Abstract

A multi-core radio frequency receiving coil structure, a multi-core radio frequency receiving apparatus, and a device. The multi-core radio frequency receiving coil structure comprises: a first receiving coil (100), configured to receive an MR relaxation signal of a first type of cores, the first receiving coil comprising a staggered center (101) located in the middle of the first receiving coil and staggered in a current direction; and a second receiving coil (200), configured to receive the MR relaxation signal of a second type or third type of cores, the second receiving coil (200) and the first receiving coil (100) being stacked, wherein the staggered center (101) is located in the vertical projection of the second receiving coil (200) in the first receiving coil (100), so as to realize orthogonal distribution of the magnetic field generated by the second receiving coil (200) and the magnetic field generated by the first receiving coil (100), such that the first receiving coil (100) and the second receiving coil (200) are decoupled. The number of channels of the radio frequency coil and the size of the coil are not limited. The radio frequency receiving coil suitable for three nuclide signals can be extended to any nuclide of interest.

Description

Multi-core radio frequency receiving coil structure, multi-core radio frequency receiving device and equipment

technical field

This application belongs to Nuclear Magnetic Resonance Imaging (English: Nuclear Magnetic Resonance Imaging (NMRI for short) imaging technology field, especially relates to a multi-core radio frequency receiving coil structure, multi-core radio frequency receiving device and magnetic resonance imaging equipment.

Background technique

At present, simultaneous acquisition of multiple nuclide signals is of great significance for NMR quantitative imaging. The inherently low signal-to-noise ratio (SIGNAL-NOISE RATIO , SNR) of non-H (hydrogen) nuclide imaging poses more challenges for the development of multinuclear imaging technology and hardware. high demands. In the design scheme of the multi-core radio frequency coil, there are mainly two types of schemes, single structure and combined structure, to realize the multi-resonance of the coil. The single structure is mainly independent coil units to achieve two or more resonant frequencies, by maintaining the isolation between different cores, this structure can be easily extended to multi-channel array designs, by increasing the frequency on each loop of the coil A notch circuit that splits frequencies to create a double or triple resonance. Realize double resonant RF coils with close frequencies by utilizing the switching function of diodes. However, due to the loss caused by the insertion of the trap element, the quality of the coil and the signal-to-noise ratio are reduced.

The scheme of realizing multi-nuclide resonance based on two or more independent physical coil structures mainly includes geometric decoupling structure and nested combination. Geometric decoupling can realize the adjustment and distribution of two separate coils in two different spaces. to each desired frequency, which allows free expansion of the selection of nuclei to multiple nuclei without losing any signal-to-noise ratio of the selected nuclei, since each coil is a single tuned coil. Extending this multi-structure, single-channel coil configuration to a multi-channel array design is quite difficult and requires swapping the coils between measurements. In designs using nested coils, dealing with the coupling of the two coil systems is a major task that has a significant impact on the quality of the signal. This coupling can be controlled to avoid performance degradation by modifying the distance or arrangement between the two coils and between each channel within a coil. However, the ability to control the coupling by adjusting the distance between the inner and outer coils may be limited by the size of the body and the limited space available within the magnet bore. Most simultaneous protocols are limited to dual-nuclide acquisition, or independent imaging of nuclides with separate coils.

technical problem

The purpose of the present application is to provide a multi-core radio frequency receiving coil structure, a multi-core radio frequency receiving device and a magnetic resonance imaging device.

technical solution

The technical scheme that the embodiment of the present application adopts is:

The first aspect provides a multi-core radio frequency receiving coil structure, including:

A first receiving coil, configured to receive an MR relaxation signal of a first type of nucleus, the first receiving coil includes an interlaced center with a current direction interleaved and located in the middle of the first receiving coil;

The second receiving coil is used to receive the MR relaxation signal of the second type or the third type of nucleus, and the second receiving coil and the first receiving coil are stacked;

Wherein, the interleaving center is located in the vertical projection of the second receiving coil in the direction of the first receiving coil, so that the magnetic field generated by the second receiving coil and the magnetic field generated by the first receiving coil are positive The intersection distribution makes decoupling between the first receiving coil and the second receiving coil.

In one of the embodiments, the first receiving coil is a butterfly structure, and the second receiving coil is a ring structure.

In one of the embodiments, the first receiving coil includes a "C"-shaped input-side line segment, an "X"-shaped middle line segment, and an output-side line segment, and the input-side line segment and the output-side line segment are arranged symmetrically , the middle line segment includes a first line segment and a second line segment that are staggered and not connected to form the interlaced center, and the two ends of the first line segment are respectively connected to the first end of the input side line segment and the The second end of the line segment on the output side is connected, and the two ends of the second line segment are respectively connected to the second end of the line segment on the input side and the first end of the line segment on the output side.

In one of the embodiments, the first receiving coil is connected with at least one first capacitor for tuning and matching the MR relaxation signals of the first kind of nuclei.

In one of the embodiments, the second receiving coil is connected with at least one second capacitor for tuning and matching the MR relaxation signal of the second type of nucleus, and at least one second capacitor for tuning and matching the third the third capacitance of the MR relaxation signal of the nuclei of the species;

Wherein, the second receiving coil resonates in the MR relaxation signal of the second type of nucleus or the MR relaxation signal of the third type of nucleus by connecting or short-circuiting the third capacitor.

The second aspect provides a multi-core radio frequency receiving device, including the above-mentioned multi-core radio frequency receiving coil structure, and the multi-core radio frequency receiving device also includes:

The first driving circuit, and the first receiving coil, are configured to provide a first driving signal to the first receiving coil, so that the first receiving coil receives and outputs an MR relaxation signal of a first type of nucleus;

The first protection circuit, and the first receiving coil, are used to control the first receiving coil to prohibit operation when its transmitting coil is working;

The second driving circuit, and the second receiving coil, are used to provide the second receiving coil with a second driving signal, so that the second receiving coil receives the MR relaxation of the second type or the third type of nuclei signal and output;

The second protection circuit, and the second receiving coil, are used to control the second receiving coil to prohibit operation when its transmitting coil is working;

The tuning circuit, together with the second receiving coil, is used to control the second receiving coil to switch between receiving MR relaxation signals of the second type of nuclei and MR relaxation signals of the third type of nuclei.

In one of the embodiments, the first drive circuit includes a first drive interface for accessing the first drive signal, a first inductor, a first diode and a first tuning capacitor, the first The anode of the diode is connected to the anode of the first drive interface, the cathode of the first diode is connected to the cathode of the first drive interface, and the first tuning capacitor is connected to the first diode connected in parallel and in series on the first receiving coil, the positive and/or negative poles of the first drive interface are connected in series with the first inductor;

The second drive circuit includes a second drive interface for accessing the second drive signal, a second inductor, a second diode and a second tuning capacitor, the anode of the second diode is connected to the The anode of the second drive interface is connected, the cathode of the second diode is connected to the cathode of the second drive interface, the second tuning capacitor is connected in parallel with the second diode, and connected in series with the On the second receiving coil, the positive pole and/or negative pole of the second driving interface is connected in series with the second inductor.

In one of the embodiments, it also includes a first output interface, a third tuning capacitor serially connected to the first receiving coil, a second output interface, and a fourth tuning capacitor serially connected to the second receiving coil , the positive pole and the negative pole of the first output interface are respectively connected to both ends of the third tuning capacitor, the first output interface is used to output the MR relaxation signal of the first type of nucleus; the second The positive pole and the negative pole of the output interface are respectively connected to both ends of the fourth tuning capacitor, and the second output interface is used to output the MR relaxation signal of the second type or the third type of nucleus.

In one of the embodiments, the first protection circuit includes a third diode, a third inductor and a first protection interface, the anode of the third diode is connected to the anode of the first output interface, The cathode of the third diode is connected to the cathode of the first output interface, the anode and/or cathode of the first protection interface is connected in series with the third inductor, and the first protection interface is used for controlling the first receiving coil to switch on a protection signal to drive the third diode to conduct when the transmitting coil is working, so as to short-circuit the first output interface;

The second protection circuit includes a fourth diode, a fourth inductor and a second protection interface, the anode of the fourth diode is connected to the anode of the second output interface, and the fourth diode The negative pole of the second output interface is connected to the negative pole of the second output interface, the positive pole and/or negative pole of the second protection interface is connected in series with the fourth inductor, and the second protection interface is used to control the second receiving coil When the transmitting coil is working, the access protection signal drives the fourth diode to conduct, so as to short-circuit the second output interface.

In one of the embodiments, the tuning circuit includes a tuning interface and a fifth tuning capacitor, the fifth tuning capacitor is connected in series with the second receiving coil, and the positive pole and the negative pole of the tuning interface are respectively connected to the The two ends of the fifth tuning capacitor, the tuning interface is connected or not connected to the tuning signal so that the fifth tuning capacitor is short-circuited or not short-circuited, so as to control the MR relaxation of the second receiving coil when receiving the second nucleus. relaxation signal and the MR relaxation signal of the third kind of nuclei.

A third aspect provides a resonance imaging device, including the above-mentioned multi-core radio frequency receiving device.

Beneficial effect

Not limited by the number of channels of the RF coil and the size of the coil. The RF surface receiver coil scheme for three nuclide signals is not limited to the imaging of ¹⁹ F, ²³ Na, ³¹ P nuclides, and can be extended to any nuclides of interest.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings that need to be used in the embodiments or exemplary technical descriptions. Obviously, the accompanying drawings in the following descriptions are only for this application. For some embodiments, those skilled in the art can also obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a multi-core radio frequency receiving coil structure provided by an embodiment of the present application;

FIG. 2 is an example circuit schematic diagram of the first receiving coil in the multi-core radio frequency receiving device provided by the embodiment of the present application;

FIG. 3 is an example circuit schematic diagram of the second receiving coil in the multi-core radio frequency receiving device provided by the embodiment of the present application;

FIG. 4 is a timing table of driving voltages of a multi-core radio frequency receiving device provided in an embodiment of the present application;

Figure 5(a) is the S11 parameter waveform of the ¹⁹ F, ²³ Na channel working in the multi-core radio frequency receiving device provided by the embodiment of the present application;

Fig. 5(b) is the S11 parameter waveform of the ³¹ P channel working in the multi-core radio frequency receiving device provided by the embodiment of the present application.

Embodiments of the present invention

In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application, and are not intended to limit the present application.

It should be noted that when an element is referred to as being “fixed” or “disposed on” another element, it may be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

It is to be understood that the terms "length", "width", "top", "bottom", "front", "rear", "left", "right", "vertical", "horizontal", "top" , "bottom", "inner", "outer" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the application and simplifying the description, rather than indicating or implying the referred device Or elements must have a certain orientation, be constructed and operate in a certain orientation, and thus should not be construed as limiting the application.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present application, "plurality" means two or more, and "several" means one or more, unless otherwise specifically defined.

Figure 1 shows a schematic structural diagram of the multi-core radio frequency receiving coil structure provided by the embodiment of the present application. For the convenience of description, only the parts related to this embodiment are shown, and the details are as follows:

A multi-core radio frequency receiving coil structure includes a first receiving coil 100 and a second receiving coil 200 . The first receiving coil 100 is used to receive a magnetic resonance (Magnetic Resonance, MR) relaxation signal of a first type of nucleus, and the first receiving coil 100 includes an interlacing center 101 located in the middle of the first receiving coil 100 with alternating current directions; The second receiving coil 200 is used to receive the MR relaxation signal of the second type or the third type of nucleus, and the second receiving coil 200 and the first receiving coil 100 are stacked; wherein, the interleaving center 101 is located at the second receiving coil 200 In the vertical projection on the direction of the first receiving coil 100, to realize that the magnetic field generated by the second receiving coil 200 and the magnetic field generated by the first receiving coil 100 are orthogonally distributed, so that between the first receiving coil 100 and the second receiving coil 200 decoupling.

The two independent receiving coils 100, 200 are connected to different directions of the drive signal TD1/TD2, specifically approximately in an orthogonal relationship, so that the currents passing through most of the conductive paths on the two coils are in an orthogonal relationship. Therefore, the first receiving coil The magnetic fields generated by the coil 100 and the second receiving coil 200 are distributed in an orthogonal manner, which realizes electromagnetic decoupling, improves the signal-to-noise ratio, and improves the quality of magnetic resonance imaging. The first receiving coil 100 and the second receiving coil 200 are stacked, and can realize the radio frequency reception of three-nuclides imaging, which is much smaller than the three-turn independent three-resonant structure, which is more conducive to the miniaturization of products. The first kind of nucleus can be ²³ Na, the second kind of nucleus can be ¹⁹ F, the third kind of nucleus can be ³¹ P, of course, it can also be ¹ H, ¹⁴ N, ¹³ C, ³⁹ K, ¹⁷ O or ¹²⁹ X, the user can adjust the length of the two coils or add other tuning devices according to the resonance frequency matched by different nuclides.

In one embodiment, the first receiving coil 100 is a butterfly structure, and the second receiving coil 200 is a ring structure. As shown in Fig. 1, the first receiving coil 100 receives the driving signal TD2 from the left side, and the second receiving coil 200 receives the driving signal TD1 from the upper side, so that at the same time, the current directions of the two coils are approximately in an orthogonal relationship. . Generally, capacitors can be arranged on the two coils to tune and match the resonance frequency of the MR relaxation signal of the corresponding nuclide. Optionally, the second receiving coil 200 has a rectangular structure or a circular structure.

In one of the embodiments, the first receiving coil 100 includes a "C"-shaped input-side segment 102, an "X"-shaped middle segment 103, and an output-side segment 104, and the input-side segment 102 and the output-side segment 104 are arranged symmetrically. , the middle line segment 103 includes a first line segment 103a and a second line segment 103b that are staggered and not connected to form the interlaced center 101, and the two ends of the first line segment 103a are respectively connected to the first end of the input side line segment 102 and the output side line segment 104 The two ends of the second line segment 103b are respectively connected to the second end of the input side line segment 102 and the first end of the output side line segment 104. Wherein, the corners of the "C"-shaped input-side line segment 102 and the output-side line segment 104 arranged symmetrically to the input-side line segment 102 may be right angles or rounded corners, which are not specifically limited.

Optionally, at least one first capacitor for tuning and matching the MR relaxation signals of the first type of nuclei is connected to the first receiving coil 100 . In this example, four first capacitors are connected in series to the first receiving coil 100, namely C1, C2, C3, and C4, wherein the capacitors C1 and C3 are connected in series to the line segment 102 on the input side, and are located at the input of the line segment 102 on the input side. On opposite sides of the port, capacitors C2 and C4 are respectively arranged at the input port and the output port of the line segment 102 on the input side, between the positive and negative poles of the input port and the output port. Optionally, at least one of the capacitors C1 , C2 , C3 , and C4 is an adjustable capacitor for adjusting the resonant frequency of the first receiving coil 100 .

In one of the embodiments, the second receiving coil 200 is connected with at least one second capacitor for tuning and matching the MR relaxation signal of the second kind of nucleus, and at least one second capacitor for tuning and matching the MR relaxation signal of the third kind of nucleus. A third capacitor for the relaxation signal. In this example, four second capacitors are connected in series on the second receiving coil 200, namely C5, C6, C7, and C9, wherein the capacitors C6 and C9 are connected in series on opposite sides of the input port of the second receiving coil 200, Capacitors C5 and C7 are respectively arranged at the input port and the output port of the second receiving coil 200 , between the positive and negative poles of the input port and the output port. The third capacitor C8 for tuning and matching the MR relaxation signal of the third type of nucleus, specifically, by connecting or short-circuiting the third capacitor C8 to realize the second receiving coil 200 resonating in the MR relaxation of the second type of nucleus signal or the MR relaxation signal of a third kind of nucleus. Optionally, at least one of the capacitors C5 , C6 , C7 , and C9 is an adjustable capacitor for adjusting the resonant frequency of the second receiving coil 200 .

The second aspect of the embodiment of the present application provides a multi-core radio frequency receiving device including the above-mentioned multi-core radio frequency receiving coil structure, and the multi-core radio frequency receiving device also includes a first drive circuit 11, a first protection circuit 12, a second drive circuit 13, a second Two protection circuit 14 and tuning circuit 15 .

The first driving circuit 11 and the first receiving coil 100 are used to provide the first receiving coil 100 with a first driving signal TD2, so that the first receiving coil 100 receives and outputs the MR relaxation signal of the first type of nucleus; the first The protection circuit 12 and the first receiving coil 100 are used to control the first receiving coil 100 to prohibit operation when the transmitting coil is working; the second driving circuit 13 and the second receiving coil 200 are used to provide the second receiving coil 200 with a second Drive signal TD1, so that the second receiving coil 200 receives and outputs the MR relaxation signal of the second type or the third type of nucleus; the second protection circuit 14 and the second receiving coil 200 are used to control the second receiving coil 200 in Operation is prohibited when the transmitting coil is in operation; the tuning circuit 15 and the second receiving coil 200 are used to control the second receiving coil 200 between receiving the MR relaxation signal of the second kind of nucleus and the MR relaxation signal of the third kind of nucleus switch.

It can be understood that the drive signal TD1/TD2 is only connected when the transmitting coil stops working, so as to avoid the receiving coil and the transmitting coil working at the same time, causing damage; and, when the transmitting coil is working, the output of the receiving coil is turned off, specifically, it can be directly Short the positive and negative poles of the output port.

In one of the embodiments, the first driving circuit 11 includes a first driving interface 112 for accessing the first driving signal TD2, a first inductor L1, a first diode D1 and a first tuning capacitor C2, the first The anode of the diode D1 is connected to the anode of the first drive interface 112, the cathode of the first diode D1 is connected to the cathode of the first drive interface 112, and the first tuning capacitor C2 is connected in parallel and in series with the first diode D1 On the first receiving coil 100, a first inductor L1 is connected in series to the positive pole and/or the negative pole of the first driving interface 112;

The second drive circuit 13 includes a second drive interface 131 for receiving the second drive signal TD1, a second inductor L2, a second diode D3 and a second tuning capacitor C5, the anode of the second diode D3 is connected to the The anode of the second drive interface 131 is connected, the cathode of the second diode D3 is connected to the cathode of the second drive interface 131, the second tuning capacitor C5 is connected in parallel with the second diode D3, and is connected in series with the second receiving coil 200 , the positive pole and/or the negative pole of the second drive interface 131 is connected in series with the second inductor L2. Optionally, both the first inductor L1 and the second inductor L2 can be one or two, if there is one, they can be connected in series to the positive pole or the negative pole of the drive interface, if there are two, the positive pole of the drive interface An inductor can be connected in series with the negative pole at the same time, which acts as an anti-interference input. Optionally, the first drive interface 112 and the second drive interface 131 are coaxial line interfaces, the inner conductor and the outer conductor of the coaxial line are respectively the positive pole and the negative pole of the drive interface, and the use of the coaxial line to transmit the driving signal is beneficial to improve Anti-interference ability, improve signal quality.

In one of the embodiments, it also includes a first output interface Na_Rx, a third tuning capacitor C4 connected in series to the first receiving coil 100, a second output interface F_Rx, and a fourth tuning capacitor connected in series to the second receiving coil 200. Capacitor C7, the positive pole and negative pole of the first output interface Na_Rx are respectively connected to both ends of the third tuning capacitor C4, the first output interface Na_Rx is used to output the MR relaxation signal of the first type of nucleus; the positive pole of the second output interface F_Rx and the negative electrode are respectively connected to both ends of the fourth tuning capacitor C7, and the second output interface F_Rx is used to output the MR relaxation signal of the second type or the third type of nucleus. The first output interface Na_Rx and the second output interface F_Rx are coaxial cable interfaces, and the inner conductor and outer conductor of the coaxial cable are respectively the positive pole and the negative pole of the output interface. Using the coaxial cable to transmit the driving signal is beneficial to improve the anti-interference ability. Improve signal quality.

In one of the embodiments, the first protection circuit 12 includes a third diode D2, a third inductor L3 and a first protection interface 121, the anode of the third diode D2 is connected to the anode of the first output interface Na_Rx, The negative pole of the third diode D2 is connected to the negative pole of the first output interface Na_Rx, the positive pole and/or negative pole of the first protection interface 121 is connected in series with the third inductor L3, and the first protection interface 121 is used to control the first receiving coil When the transmitting coil of 100 is working, the first protection signal TR2 is connected to drive the third diode D2 to conduct, so as to short-circuit the first output interface Na_Rx, so that the first receiving coil 100 is turned off, so as to protect itself and the subsequent circuit;

The second protection circuit 14 includes a fourth diode D4, a fourth inductor L4 and a second protection interface 141, the anode of the fourth diode D4 is connected to the anode of the second output interface F_Rx, and the anode of the fourth diode D4 The negative pole is connected to the negative pole of the second output interface F_Rx, the positive pole and/or negative pole of the second protection interface 141 is connected in series with a fourth inductor L4, and the second protection interface 141 is used to control the second receiving coil 200 when its transmitting coil is working , the second protection signal TR1 is connected to drive the fourth diode D4 to short-circuit the second output interface F_Rx, so that the output of the second receiving coil 200 is turned off, so as to protect itself and the subsequent circuit.

Optionally, both the third inductor L3 and the fourth inductor L4 can be one or two, if there is one, they can be connected in series to the positive or negative pole of the output interface, if there are two, the positive pole of the output interface An inductor can be connected in series with the negative pole at the same time, which acts as an anti-interference input. Optionally, the first protection interface 121 and the second protection interface 141 are coaxial line interfaces, the inner conductor and the outer conductor of the coaxial line are respectively the positive pole and the negative pole of the protection interface, and the use of the coaxial line to transmit the drive signal is beneficial to improve Anti-interference ability, improve signal quality.

In one of the embodiments, the tuning circuit 15 includes a tuning interface 151 and a fifth tuning capacitor C8, the fifth tuning capacitor C8 is connected in series with the second receiving coil 200, and the positive pole and the negative pole of the tuning interface 151 are respectively connected to the fifth tuning capacitor At both ends of C8, the tuning interface 151 connects or does not connect the tuning signal so that the fifth tuning capacitor C8 is short-circuited or not short-circuited, so as to control the second receiving coil 200 to receive the MR relaxation signal of the second type of nucleus and the third Switch between species of nuclei with MR relaxation signals. Optionally, the tuning interface 151 is a coaxial interface, and the tuning signal P_Rx is a voltage signal, which is equivalent to short-circuiting or not short-circuiting the fifth tuning capacitor C8 when the coaxial interface is connected to or not connected to a voltage; In an embodiment, the tuning interface 151 may be a switching element, such as a relay.

As shown in Figure 2 and Figure 3, combined with Figure 4, in Figure 4, Tx indicates the power supply of each control circuit in the transmitting state; Rx indicates the input voltage of each circuit when the coil is in the receiving state.

The working sequence of the first driving signal TD2 and the second driving signal TD1 is the same. When the first type of nuclear MR transmitting coil is working, in order to protect the first receiving coil 100, it is necessary to make the first protection signal TR2=5V, and the third diode D2 is turned on, so that the first output interface Na_Rx is short-circuited. In order to ensure that the first receiving coil 100 resonates at the frequency of the MR relaxation signal of the first type of nucleus, in the receiving state, the first driving signal TD2=-30V and the first protection signal TR2=-30V. At this time, the first diode D1 and the third diode D2 are not conducting, and their tuning and matching are realized through the capacitors C1, C2, C3, and C4.

Similar to the working principle of the first receiving coil 100, when the second type of nuclear MR transmitting coil is working, in order to protect the second receiving coil 200, it is necessary to make the second protection signal TR1=5V, the fourth diode D4 conducts, and the second The second output interface F_Rx is short-circuited to play a protective role. When the second receiving coil 200 is working, the second protection signal TR1=-30V, the fourth diode D4 is not conducting, the second driving signal TD1=-30V, the second diode D3 is not conducting, the capacitors C5, C6, C7, C8, C9 participate in the MR relaxation signal resonance of the second kind of nuclei. And when the second drive signal TD1 and the first drive signal TD2=5V, the capacitor C2 is short-circuited, and only the capacitors C1, C3, and C4 are left in the first receiving coil 100 to participate in resonance; therefore, the resonant frequency of the first receiving coil 100 is offset. When the second driving signal TD1=5V and the tuning signal P_Rx=-30V, the capacitor C8 is short-circuited in the second receiving coil 200 at this time, and the capacitors C5, C6, C7, and C9 participate in the MR relaxation signal of the third type of nucleus The resonance of is not at the resonance point of the MR relaxation signal of the first and second types of nuclei, and at this time the MR relaxation signal of the third type of nucleus resonates.

A third aspect of the embodiments of the present application provides a resonance imaging device, including the above-mentioned multi-core radio frequency receiving device.

The array coil structure of the embodiment provided in this application has been tested experimentally, and the test results show that each channel of ¹⁹ F, ²³ Na, and ³¹ P has achieved good tuning and matching. When ¹⁹ F and ²³ Na work at the same time, each The channel matching is less than -15 dB, as shown in the curves S11 and S44 in Figure 5(a); when ^{the 31} P channel is working, as shown in the curve S33 in Figure 5(b), the matching is close to -20 dB, and the experimental results are passed It is proved that the three-core radio frequency receiving coil scheme proposed in this application is feasible, and the resonance of ¹⁹ F, ²³ Na, and ³¹ P is realized.

Compared with the above-mentioned multi-core radio frequency receiving coil structure, multi-core radio frequency receiving device and magnetic resonance imaging equipment, compared with the existing double-tuned radio frequency array coil structure and three-turn independent triple-resonant structure, this application proposes a radio frequency receiving coil that supports triple-nuclide imaging structure, on the basis of the combination of two independent coil structures, the free switching of the operating frequency of the three nuclides is realized, and the three nuclear magnetic resonance imaging is realized, and the volume is small, which is conducive to product miniaturization; decoupling between the two, good signal quality, and this method can be extended to any nuclide of interest.

The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still implement the foregoing embodiments Modifications to the technical solutions described in the examples, or equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the application, and should be included in the Within the protection scope of this application.

Claims

A multi-core radio frequency receiving coil structure is characterized in that it comprises:

A first receiving coil, configured to receive an MR relaxation signal of a first type of nucleus, the first receiving coil includes an interlaced center with a current direction interleaved and located in the middle of the first receiving coil;

The second receiving coil is used to receive the MR relaxation signal of the second type or the third type of nucleus, and the second receiving coil and the first receiving coil are stacked;

Wherein, the interleaving center is located in the vertical projection of the second receiving coil in the direction of the first receiving coil, so that the magnetic field generated by the second receiving coil and the magnetic field generated by the first receiving coil are positive The intersection distribution makes decoupling between the first receiving coil and the second receiving coil.
The multi-core radio frequency receiving coil structure according to claim 1, wherein the first receiving coil is a butterfly structure, and the second receiving coil is a ring structure.
The multi-core radio frequency receiving coil structure according to claim 1, wherein the first receiving coil includes a "C"-shaped input side line segment, an "X"-shaped middle line segment and an output side line segment, the input The side line segment is arranged symmetrically with the output side line segment, the middle line segment includes a first line segment and a second line segment that are interleaved but not connected to form the interlaced center, and the two ends of the first line segment are respectively connected to the The first end of the line segment on the input side is connected to the second end of the line segment on the output side, and the two ends of the second line segment are respectively connected to the second end of the line segment on the input side and the first end of the line segment on the output side.
The multi-core radio frequency receiving coil structure according to any one of claims 1 to 3, wherein the first receiving coil is connected with at least one MR relaxation signal for tuning and matching the first type of core first capacitor.
The multi-core radio frequency receiving coil structure according to claim 1 or 2, wherein the second receiving coil is connected with at least one second capacitor for tuning and matching the MR relaxation signal of the second type of core , and at least one third capacitor for tuning and matching the MR relaxation signal of the third kind of nuclei;

Wherein, the second receiving coil resonates in the MR relaxation signal of the second type of nucleus or the MR relaxation signal of the third type of nucleus by connecting or short-circuiting the third capacitor.
A multi-core radio frequency receiving device, characterized in that it comprises the multi-core radio frequency receiving coil structure according to any one of claims 1 to 5, the multi-core radio frequency receiving device further comprising:

The first driving circuit, and the first receiving coil, are configured to provide a first driving signal to the first receiving coil, so that the first receiving coil receives and outputs an MR relaxation signal of a first type of nucleus;

The first protection circuit, and the first receiving coil, are used to control the first receiving coil to prohibit operation when its transmitting coil is working;

The second driving circuit, and the second receiving coil, are used to provide the second receiving coil with a second driving signal, so that the second receiving coil receives the MR relaxation of the second type or the third type of nuclei signal and output;

The second protection circuit, and the second receiving coil, are used to control the second receiving coil to prohibit operation when its transmitting coil is working;

The tuning circuit, together with the second receiving coil, is used to control the second receiving coil to switch between receiving MR relaxation signals of the second type of nuclei and MR relaxation signals of the third type of nuclei.
The multi-core radio frequency receiving device according to claim 6, wherein the first drive circuit comprises a first drive interface for accessing the first drive signal, a first inductor, a first diode and The first tuning capacitor, the anode of the first diode is connected to the anode of the first drive interface, the cathode of the first diode is connected to the cathode of the first drive interface, and the first tuning The capacitor is connected in parallel with the first diode and connected in series with the first receiving coil, and the positive and/or negative electrodes of the first driving interface are connected in series with the first inductor;

The second drive circuit includes a second drive interface for accessing the second drive signal, a second inductor, a second diode and a second tuning capacitor, the anode of the second diode is connected to the The anode of the second drive interface is connected, the cathode of the second diode is connected to the cathode of the second drive interface, the second tuning capacitor is connected in parallel with the second diode, and connected in series with the On the second receiving coil, the positive pole and/or negative pole of the second driving interface is connected in series with the second inductor.
The multi-core radio frequency receiving device according to claim 6 or 7, further comprising a first output interface, a third tuning capacitor connected in series on the first receiving coil, a second output interface, and a second output interface connected in series to the first receiving coil. The fourth tuning capacitor on the second receiving coil, the positive pole and the negative pole of the first output interface are respectively connected to the two ends of the third tuning capacitor, and the first output interface is used to output the first type of The MR relaxation signal of the nucleus; the positive pole and the negative pole of the second output interface are respectively connected to the two ends of the fourth tuning capacitor, and the second output interface is used to output the second type or the third type MR relaxation signal of the nucleus.
The multi-core radio frequency receiving device according to claim 8, wherein the first protection circuit comprises a third diode, a third inductor and a first protection interface, and the anode of the third diode is connected to the The positive pole of the first output interface is connected, the negative pole of the third diode is connected to the negative pole of the first output interface, and the positive pole and/or negative pole of the first protection interface is connected in series with the third inductor , the first protection interface is used to control the first receiving coil to receive a protection signal to drive the third diode to conduct when the first receiving coil is working, so as to short-circuit the first output interface;

The second protection circuit includes a fourth diode, a fourth inductor and a second protection interface, the anode of the fourth diode is connected to the anode of the second output interface, and the fourth diode The negative pole of the second output interface is connected to the negative pole of the second output interface, the positive pole and/or negative pole of the second protection interface is connected in series with the fourth inductor, and the second protection interface is used to control the second receiving coil When the transmitting coil is working, the access protection signal drives the fourth diode to conduct, so as to short-circuit the second output interface.
The multi-core radio frequency receiving device according to claim 6 or 7, wherein the tuning circuit includes a tuning interface and a fifth tuning capacitor, the fifth tuning capacitor is connected in series with the second receiving coil, the The positive pole and the negative pole of the tuning interface are respectively connected to both ends of the fifth tuning capacitor, and the tuning interface is connected to or not connected to a tuning signal so that the fifth tuning capacitor is short-circuited or not short-circuited, so as to control the second The receive coil is switched between receiving MR relaxation signals of the second kind of nuclei and MR relaxation signals of the third kind of nuclei.
A magnetic resonance imaging device, characterized by comprising the multi-core radio frequency receiving device according to any one of claims 6 to 10.