Birdcage type double-frequency emission coil, magnetic resonance double-frequency emission system and magnetic resonance equipment

Abstract

The invention relates to the technical field of magnetic resonance, and provides a birdcage type dual-frequency emission coil, a magnetic resonance dual-frequency emission system and magnetic resonance equipment, in the birdcage type dual-frequency emission coil, a first end ring and a second end ring are connected through a plurality of parallel linear conductors; each linear conductor is provided with a diode and two capacitors, one capacitor is close to the first end ring, the other capacitor is close to the second end ring, and the diode is located between the two capacitors; the first end ring or the second end ring is also connected with a plurality of balun components, and the plurality of balun components are correspondingly connected with a high-frequency signal input end, a high-frequency signal output end, a low-frequency signal input end and a low-frequency signal output end of the frequency switching control module one by one so as to integrate high-frequency signals and low-frequency signals to be transmitted in a broadband range; the high-frequency and low-frequency integrated magnetic field generator has high-frequency and low-frequency working frequencies, the two working frequencies are integrated, the generated radio-frequency magnetic field is relatively uniform and can bear relatively high voltage, and the application scene is effectively expanded.

Description

Technical Field

[0001] The present invention relates to the field of magnetic resonance technology, and more specifically to a birdcage-type dual-frequency transmitting coil, a magnetic resonance dual-frequency transmitting system and a magnetic resonance device. Background Art

[0002] Magnetic resonance imaging systems are non-invasive, non-ionizing, and radiation-free, and are widely used in the field of clinical medicine. Among them, the transmitting coil is an important component of the magnetic resonance imaging system, which will directly affect the image signal-to-noise ratio and play a vital role in the imaging quality. At present, various transmitting coils have been developed on the market for the different body shapes of humans and animals. However, most transmitting coils on the market are single-frequency, but there is still a large gap in dual-frequency integrated design, especially in the field of magnetic resonance research. The application of single frequency has obvious limitations, the development cost is high, and the application scenarios are limited. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a birdcage-type dual-frequency transmitting coil, a magnetic resonance dual-frequency transmitting system and a magnetic resonance device in view of the above-mentioned defects of the prior art.

[0004] The technical solution adopted by the present invention to solve its technical problem is:

[0005] On the one hand, the present invention provides a birdcage-type dual-frequency transmitting coil, which includes a frequency switching control module and an axially distributed first end ring and a second end ring, wherein the first end ring and the second end ring are connected by a plurality of mutually parallel linear conductors; each of the linear conductors is provided with a diode and two capacitors, wherein one of the capacitors is close to the first end ring, wherein the other of the capacitors is close to the second end ring, and the diode is located between the two capacitors; the frequency switching control module has a high-frequency signal input terminal, a high-frequency signal output terminal, a low-frequency signal input terminal and a low-frequency signal output terminal, and the first end ring or the second end ring is further connected to a plurality of balun components, and the plurality of balun components are connected one by one with the high-frequency signal input terminal, the high-frequency signal output terminal, the low-frequency signal input terminal and the low-frequency signal output terminal, so as to integrate the high-frequency signal and the low-frequency signal for transmission within a wide frequency range.

[0006] In some embodiments, the plurality of linear conductors are arranged at equal intervals along the circumference of the first end ring and the second end ring, the first end of each linear conductor is connected to the first end ring, and the second end of each linear conductor is connected to the second end ring.

[0007] In some embodiments, the number of the linear conductors is twelve; the positive and negative connection directions of the diodes on six of the linear conductors are consistent and opposite to the positive and negative connection directions of the diodes on the other six linear conductors.

[0008] In some embodiments, the signal frequencies of the high-frequency signal input terminal and the high-frequency signal output terminal are consistent; the signal frequencies of the low-frequency signal input terminal and the low-frequency signal output terminal are consistent.

[0009] On the other hand, the present invention further provides a magnetic resonance dual-frequency transmitting system, wherein the magnetic resonance dual-frequency transmitting system comprises the birdcage dual-frequency transmitting coil as described in any one of the above items.

[0010] In some embodiments, the magnetic resonance dual-frequency transmission system also includes a transmitting coil control module, which is connected to the frequency switching control module; the transmitting coil control module is used to obtain the current signal state and output a switching drive signal to the frequency switching control module according to the current signal state, and the frequency switching control module switches the current signal state according to the switching drive signal.

[0011] In some embodiments, the frequency switching control module includes a high-frequency signal circuit and a low-frequency signal circuit; the high-frequency signal circuit has a first DC driving end, and the transmitting coil control module is connected to the first DC driving end through a first DC driving cable; the low-frequency signal circuit has a second DC driving end, and the transmitting coil control module is connected to the second DC driving end through a second DC driving cable; the transmitting coil control module is also connected to each linear conductor through a third DC driving cable to drive the corresponding diode on the linear conductor to turn on.

[0012] In some embodiments, the high-frequency signal input terminal and the high-frequency signal output terminal are both arranged in a high-frequency signal circuit, and the high-frequency signal circuit also has two first signal transmission terminals, and the two first signal transmission terminals are correspondingly connected to the transmitting coil control module through two first connectors, and the high-frequency signal input terminal and the high-frequency signal output terminal are correspondingly connected to the two balun components one by one through two second connectors.

[0013] In some embodiments, the low-frequency signal input terminal and the low-frequency signal output terminal are both arranged in a low-frequency signal circuit, and the low-frequency signal circuit also has two second signal transmission terminals, and the two second signal transmission terminals are correspondingly connected to the transmitting coil control module through two third connectors, and the low-frequency signal input terminal and the low-frequency signal output terminal are correspondingly connected to the other two balun components one by one through two fourth connectors.

[0014] On the other hand, the present invention further provides a magnetic resonance device, comprising the magnetic resonance dual-frequency transmission system as described in any one of the above items.

[0015] The beneficial effects of the present invention are as follows: Different from the prior art, in the birdcage-type dual-frequency transmitting coil of the present invention, the first end ring and the second end ring are connected by a plurality of mutually parallel linear conductors; a diode and two capacitors are provided on each linear conductor, one of which is close to the first end ring, the other of which is close to the second end ring, and the diode is located between the two capacitors; the first end ring or the second end ring is also connected to a plurality of balun components, and the plurality of balun components are connected one by one with the high-frequency signal input end, the high-frequency signal output end, the low-frequency signal input end and the low-frequency signal output end of the frequency switching control module to integrate the high-frequency signal and the low-frequency signal for transmission within a wide frequency range; under this structure, the birdcage-type dual-frequency transmitting coil has two operating frequencies, high frequency and low frequency, and the two operating frequencies are designed in an integrated manner, the radio frequency magnetic field generated is relatively uniform, can withstand a higher voltage, and the application scenarios are effectively expanded. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 1 is a three-dimensional birdcage-shaped schematic diagram of a birdcage-shaped dual-frequency transmitting coil in an embodiment of the present invention;

[0017] Figure 2 1 is a schematic diagram of a flattened and unfolded birdcage-type dual-frequency transmitting coil in an embodiment of the present invention;

[0018] Figure 3 is a circuit structure diagram of multiple linear conductors in an embodiment of the present invention;

[0019] Figure 4 is a schematic diagram of a birdcage-type dual-frequency transmitting coil installed on a coil cylinder in an embodiment of the present invention;

[0020] Figure 5 is another schematic diagram of the birdcage-type dual-frequency transmitting coil installed on the coil cylinder in an embodiment of the present invention;

[0021] Figure 6 is a block diagram of a magnetic resonance dual-frequency transmission system in an embodiment of the present invention;

[0022] Figure 7 is a circuit structure diagram of a frequency switching control module in an embodiment of the present invention;

[0023] Names and serial numbers in the figure: birdcage-type dual-frequency transmitting coil-10; frequency switching control module-1; first end ring-2; second end ring-3; linear conductor-4; balun component-5; coil cylinder-20; convex ring-21; magnetic resonance dual-frequency transmitting system-30; transmitting coil control module-31; high-frequency signal circuit-11; low-frequency signal circuit-12. DETAILED DESCRIPTION

[0024] The terms "first", "second", "third" and "fourth" etc. in the specification and claims of the present invention and the drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or devices.

[0025] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0026] "Multiple" means two or more. "And / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the related objects are in an "or" relationship.

[0027] Moreover, the terms "up, down, front, back, left, right, upper end, lower end" etc. indicating directions are all based on the posture and position of the device or equipment described in this solution during normal use.

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the following will be described clearly and completely in combination with the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are partial embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of the present invention.

[0029] Embodiment 1: The embodiment of the present invention provides a birdcage type dual-frequency transmitting coil 10, such as Figures 1 to 3As shown in , the birdcage-type dual-frequency transmitting coil 10 includes a frequency switching control module 1 and an axially distributed first end ring 2 and a second end ring 3, the first end ring 2 and the second end ring 3 are connected by a plurality of mutually parallel linear conductors 4; each linear conductor 4 is provided with a diode and two capacitors, one of which is close to the first end ring 2, the other of which is close to the second end ring 3, and the diode is located between the two capacitors; the frequency switching control module 1 has a high-frequency signal input terminal, a high-frequency signal output terminal, a low-frequency signal input terminal and a low-frequency signal output terminal, and the first end ring 2 or the second end ring 3 is also connected to a plurality of balun components 5, and the plurality of balun components 5 are connected one by one with the high-frequency signal input terminal, the high-frequency signal output terminal, the low-frequency signal input terminal and the low-frequency signal output terminal to integrate the high-frequency signal and the low-frequency signal to be transmitted within a wide frequency range. Under this structure, the birdcage-type dual-frequency transmitting coil 10 has two working frequencies, high frequency and low frequency, and these two working frequencies are designed in an integrated manner, the generated radio frequency magnetic field is relatively uniform, can withstand a higher voltage, and the application scenarios are effectively expanded.

[0030] In this embodiment, the number of linear conductors 4 is twelve; the twelve linear conductors 4 are arranged and distributed at equal intervals along the circumference of the first end ring 2 and the second end ring 3, and the first end of each linear conductor 4 is connected to the first end ring 2, and the second end of each linear conductor 4 is connected to the second end ring 3. The positive and negative connection directions of the diodes on six linear conductors 4 are consistent and opposite to the positive and negative connection directions of the diodes on the other six linear conductors 4. For example, the positive poles of the diodes on the six linear conductors 4 are connected to the second end ring 3 and the negative poles are connected to the first end ring 2, while the positive poles of the diodes on the other six linear conductors 4 are connected to the first end ring 2 and the negative poles are connected to the second end ring 3. Thus, bidirectional control is achieved, effectively improving the flexibility and reliability of the birdcage-type dual-frequency transmitting coil 10, and ensuring the stable transmission of high-frequency signals and low-frequency signals. Specifically, the linear conductor 4 is an antenna. The number of balun components 5 is four, and the four balun components 5 are all connected to the second end ring 3 and are distributed at intervals. The structure and layout of the four balun components 5 are as follows: Figure 2 As shown in . The birdcage type dual-frequency transmitting coil 10 allows orthogonal excitation and orthogonal reception, and compared with line excitation, can save half of the RF power, effectively reduce the human body absorption rate (SAR), and can generate a uniform transverse magnetic field, suitable for working in the orthogonal mode.

[0031] It should be noted that in order for the birdcage type dual-frequency transmitting coil 10 to achieve the best transmitting effect and obtain the best uniform field, the values ​​of all the capacitors on the linear conductor 4 need to be as consistent as possible, so that the conductors on the birdcage type dual-frequency transmitting coil 10 can be evenly divided to generate a uniform radio frequency electromagnetic field in the birdcage type dual-frequency transmitting coil 10.

[0032] Among them, the signal frequencies of the high-frequency signal input end and the high-frequency signal output end are consistent; the signal frequencies of the low-frequency signal input end and the low-frequency signal output end are consistent. For example, the signal frequencies of the high-frequency signal input end and the high-frequency signal output end are both 63.86Mhz. At a frequency of 63.86Mhz, the characteristics of the human body containing hydrogen elements and the amount of hydrogen elements contained in the human body are utilized, and according to the principle of magnetic resonance, the structure of the human body is displayed in the form of an image based on the H1 element. For another example, the signal frequencies of the low-frequency signal input end and the low-frequency signal output end are both 16Mhz. At a frequency of 16Mhz, C13 is a stable isotope that can be detected by magnetic resonance imaging. Based on super technology, the C13 element is amplified 100,000 times, and the metabolites in the process of disease variation can be monitored in vivo, non-invasively, and in real time, thereby achieving the corresponding detection purpose. The technical solution of this embodiment can effectively meet different radio frequency detection needs by integrating high-frequency 63.86Mhz and low-frequency 16Mhz in one transmitting coil.

[0033] It should be noted that, depending on different actual application requirements, the signal frequencies of the high-frequency signal input terminal and the high-frequency signal output terminal, and the signal frequencies of the low-frequency signal input terminal and the low-frequency signal output terminal can also select other suitable frequencies, and are not limited to the examples in this embodiment.

[0034] When applied, such as Figure 4 and Figure 5 As shown in , the birdcage-type dual-frequency transmitting coil 10 is arranged on a coil cylinder 20, for example, laid on the outside of the coil cylinder 20. The copper between the first end ring 2 and the second end ring 3 is 30mm wide and 2OZ thick; the capacitor uses a large-package, high-Q ceramic capacitor with a withstand voltage value of up to 2500V, so that the birdcage-type dual-frequency transmitting coil 10 has good withstand voltage and current characteristics, and the high power resistance and reliability are greatly improved. Specifically, the outer side of the coil cylinder 20 is provided with two convex rings 21 distributed along its axial direction, and the distance between the two convex rings 21 is 555mm, so that the birdcage-type dual-frequency transmitting coil 10 is sleeved on the outer side of the coil cylinder 20 and located between the two convex rings 21. The aperture of the coil cylinder 20 is 300mm, and the volume is small. The coil cylinder 20 is made of glass fiber reinforced plastic, which has the characteristics of light weight, high strength and corrosion resistance, which helps to achieve a good thermal protection effect under instantaneous ultra-high temperature conditions, and the application effect is better.

[0035] Embodiment 2: The embodiment of the present invention provides a magnetic resonance dual-frequency transmission system 30, such as Figure 6 As shown in , the magnetic resonance dual-frequency transmitting system 30 includes the birdcage dual-frequency transmitting coil 10 provided in the first embodiment.

[0036] In this embodiment, the magnetic resonance dual-frequency transmitting system 30 further includes a transmitting coil control module 31, which is connected to the frequency switching control module 1. The transmitting coil control module 31 is used to obtain the current signal state and output a switching drive signal to the frequency switching control module 1 according to the current signal state. The frequency switching control module 1 switches the current signal state according to the switching drive signal, thereby realizing the switching of the two working frequencies.

[0037] Specifically, the frequency switching control module 1 includes a high-frequency signal circuit 11 and a low-frequency signal circuit 12. The high-frequency signal circuit 11 is used to transmit and receive high-frequency signals, and the low-frequency signal circuit 12 is used to transmit and receive low-frequency signals.

[0038] The high-frequency signal circuit 11 has a first DC driving end, and the transmitting coil control module 31 is connected to the first DC driving end through a first DC driving cable. The high-frequency signal input end and the high-frequency signal output end are both provided in the high-frequency signal circuit 11. The high-frequency signal circuit 11 also has two first signal transmission ends, and the two first signal transmission ends are connected to the transmitting coil control module 31 through two first connectors. The high-frequency signal input end and the high-frequency signal output end are connected to the two balun components 5 one by one through two second connectors. Figure 7 When it is necessary to receive or transmit a frequency of 63.86Mhz, a voltage and current are applied to DC driver 1 to control D1 / D2 to be turned on, so that a 63.86Mhz frequency signal can be received or transmitted.

[0039] The low-frequency signal circuit 12 has a second DC driving end, and the transmitting coil control module 31 is connected to the second DC driving end through a second DC driving cable. The low-frequency signal input end and the low-frequency signal output end are both arranged in the low-frequency signal circuit 12. The low-frequency signal circuit 12 also has two second signal transmission ends, which are connected to the transmitting coil control module 31 through two third connectors. The low-frequency signal input end and the low-frequency signal output end are connected to the other two balun components 5 through two fourth connectors. Figure 7 When it is necessary to receive or transmit a frequency of 16Mhz, a voltage and current are applied to DC driver 2 to control D3 / D4 to be turned on, so that a 16Mhz frequency signal can be received or transmitted.

[0040] In this embodiment, the first connector, the second connector, the third connector and the fourth connector are all N-type female connectors.

[0041] The transmitting coil control module 31 is also connected to each linear conductor 4 through a third DC drive cable to drive the diode on the corresponding linear conductor 4 to conduct, thereby making the entire birdcage dual-frequency transmitting coil 10 work.

[0042] In this embodiment, the transmitting coil control module 31 receives the radio frequency pulses transmitted from the system and distributes the power to the Q (output) line and I (input) line of the same frequency. When the birdcage-type dual-frequency transmitting coil 10 is used for self-transmission and self-reception, the received radio frequency signal is amplified in one stage.

[0043] Embodiment 3: The embodiment of the present invention provides a magnetic resonance device, which includes the magnetic resonance dual-frequency transmitting system 30 provided in Embodiment 2. The magnetic resonance dual-frequency transmitting system 30 provided in Embodiment 2 is applied, so that the magnetic resonance device has two operating frequencies, high frequency and low frequency, which effectively meets different radio frequency detection requirements.

[0044] It should be understood that, for ordinary technical workers in the field, improvements or changes can be made based on the above description, and all these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A birdcage dual-frequency transmitting coil, characterized in that: The birdcage-type dual-frequency transmitting coil includes a frequency switching control module and a first end ring and a second end ring distributed axially, wherein the first end ring and the second end ring are connected by a plurality of mutually parallel linear conductors; a diode and two capacitors are provided on each of the linear conductors, wherein one of the capacitors is close to the first end ring, wherein the other of the capacitors is close to the second end ring, and the diode is located between the two capacitors; the frequency switching control module has a high-frequency signal input terminal, a high-frequency signal output terminal, a low-frequency signal input terminal and a low-frequency signal output terminal, and the first end ring or the second end ring is further connected to a plurality of balun components, and the plurality of balun components are connected one by one with the high-frequency signal input terminal, the high-frequency signal output terminal, the low-frequency signal input terminal and the low-frequency signal output terminal, so as to integrate the high-frequency signal and the low-frequency signal for transmission within a wide frequency range.

2. The birdcage dual-frequency transmitting coil according to claim 1, characterized in that: The plurality of linear conductors are arranged and distributed at equal intervals along the circumference of the first end ring and the second end ring, the first end of each linear conductor is connected to the first end ring, and the second end of each linear conductor is connected to the second end ring.

3. The birdcage dual-frequency transmitting coil according to claim 1, characterized in that: The number of the linear conductors is twelve; the positive and negative connection directions of the diodes on six of the linear conductors are consistent and opposite to the positive and negative connection directions of the diodes on the other six linear conductors.

4. The birdcage dual-frequency transmitting coil according to any one of claims 1 to 3, characterized in that: The signal frequencies of the high-frequency signal input end and the high-frequency signal output end are consistent; the signal frequencies of the low-frequency signal input end and the low-frequency signal output end are consistent.

5. A magnetic resonance dual-frequency transmission system, characterized in that: The magnetic resonance dual-frequency transmitting system comprises the birdcage dual-frequency transmitting coil according to any one of claims 1 to 4.

6. The magnetic resonance dual-frequency transmission system according to claim 5, characterized in that: The magnetic resonance dual-frequency transmitting system also includes a transmitting coil control module, which is connected to the frequency switching control module; the transmitting coil control module is used to obtain the current signal state and output a switching drive signal to the frequency switching control module according to the current signal state, and the frequency switching control module switches the current signal state according to the switching drive signal.

7. The magnetic resonance dual-frequency transmission system according to claim 6, characterized in that: The frequency switching control module includes a high-frequency signal circuit and a low-frequency signal circuit; the high-frequency signal circuit has a first DC driving end, and the transmitting coil control module is connected to the first DC driving end through a first DC driving cable; the low-frequency signal circuit has a second DC driving end, and the transmitting coil control module is connected to the second DC driving end through a second DC driving cable; the transmitting coil control module is also connected to each linear conductor through a third DC driving cable to drive the corresponding diode on the linear conductor to conduct.

8. The magnetic resonance dual-frequency transmission system according to claim 7, characterized in that: The high-frequency signal input terminal and the high-frequency signal output terminal are both arranged in the high-frequency signal circuit. The high-frequency signal circuit also has two first signal transmission terminals. The two first signal transmission terminals are correspondingly connected to the transmitting coil control module through two first connectors. The high-frequency signal input terminal and the high-frequency signal output terminal are correspondingly connected to the two balun components one by one through two second connectors.

9. The magnetic resonance dual-frequency transmission system according to claim 7 or 8, characterized in that: The low-frequency signal input terminal and the low-frequency signal output terminal are both arranged in the low-frequency signal circuit. The low-frequency signal circuit also has two second signal transmission terminals. The two second signal transmission terminals are correspondingly connected to the transmitting coil control module through two third connectors. The low-frequency signal input terminal and the low-frequency signal output terminal are correspondingly connected to the other two balun components one by one through two fourth connectors.

10. A magnetic resonance device, characterized in that: The magnetic resonance device comprises the magnetic resonance dual-frequency transmission system according to any one of claims 5 to 9.

Images