CN109738839B - Radio frequency coil system applied to rotating magnetic resonance - Google Patents
Radio frequency coil system applied to rotating magnetic resonance Download PDFInfo
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- CN109738839B CN109738839B CN201811640940.1A CN201811640940A CN109738839B CN 109738839 B CN109738839 B CN 109738839B CN 201811640940 A CN201811640940 A CN 201811640940A CN 109738839 B CN109738839 B CN 109738839B
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- 230000003321 amplification Effects 0.000 claims abstract description 7
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 7
- 238000010586 diagram Methods 0.000 description 3
- 238000002595 magnetic resonance imaging Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000008054 signal transmission Effects 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
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Abstract
The invention relates to a radio frequency coil system applied to rotary magnetic resonance, which comprises a magnet, a power divider, a radio frequency transmitting coil, a radio frequency receiving coil, a radio frequency shielding layer and a signal amplification and control system, wherein the magnet rotates around the center, the power divider is connected with the radio frequency transmitting coil, the radio frequency transmitting coil is circular, the radio frequency receiving coil is a multi-channel coil, the radio frequency shielding layer is positioned on two poles of the magnet, the signal amplification and control system is used for amplifying a magnetic resonance signal of the radio frequency receiving coil, providing a driving signal of the radio frequency receiving coil and selecting a signal channel for the radio frequency receiving coil when the magnet rotates. The invention can make the application range of the radio frequency coil wider.
Description
Technical Field
The invention relates to the technical field of medical instruments, in particular to a radio frequency coil system applied to rotary magnetic resonance.
Background
In modern medical technology, a magnetic resonance imaging system is already a common medical device. The performance of the radio frequency coil, which is an integral part of the system, has a significant impact on the performance of the magnetic resonance imaging system. The existing design of radio frequency coils mainly has structures of an orthogonal flat plate type, a straight wire type and the like, in the structures, all coils are fixed on a magnet of a magnetic resonance system, and according to the physical principle, the radio frequency coil needs a good radio frequency environment to ensure that the resonance frequency of the coil cannot be changed, so that the radio frequency coils belong to fixed radio frequency coils.
With the continuous progress of medical technology, a fixed radio frequency coil cannot meet the requirements, and sometimes a mobile radio frequency coil is needed, for example, the chinese invention patent (CN 103744041A) discloses a radio frequency coil device applied to magnetic resonance imaging, which comprises a power distributor, an upper magnet and a lower magnet, and further comprises two longitudinally arranged radio frequency coil units, an upper radio frequency shielding layer and a lower radio frequency shielding layer, wherein the radio frequency coil units are connected with the power distributor; the upper radio frequency shielding layer and the lower radio frequency shielding layer are respectively positioned at the upper side and the lower side of the radio frequency coil unit, and are parallel to each other and are respectively arranged on the upper magnet and the lower magnet; the radio frequency coil unit, the upper radio frequency shielding layer and the lower radio frequency shielding layer are in centrosymmetric shapes. Although the conversion efficiency of the radio frequency coil unit can be improved, the moving range of the radio frequency coil is limited, and the resonant frequency of the radio frequency coil is greatly changed after the moving range is exceeded, so that the wide application of the radio frequency coil is influenced.
Disclosure of Invention
Therefore, the technical problem to be solved by the present invention is to overcome the problem in the prior art that the application range of the rf coil is narrow due to the easy shift of the resonant frequency, so as to provide an rf coil system applied to rotating magnetic resonance, which can avoid the shift of the resonant frequency and expand the application range.
In order to solve the above technical problems, the present invention provides a radio frequency coil system for rotational magnetic resonance, which comprises a magnet, a power divider, a radio frequency transmitting coil, a radio frequency receiving coil, a radio frequency shielding layer, and a signal amplifying and controlling system, wherein the magnet rotates about a center, the power divider is coupled to the radio frequency transmit coil, the radio frequency transmit coil and the radio frequency receive coil are both located in the plane of rotation of the magnet, and the radio frequency transmitting coil is placed in the vertical direction of the magnet rotating plane, the radio frequency transmitting coil is circular, the radio frequency receiving coil is a multi-channel coil, the radio frequency shielding layer is positioned on two poles of the magnet, the signal amplification and control system is used for amplifying the magnetic resonance signal of the radio frequency receiving coil, providing a driving signal of the radio frequency receiving coil and selecting a signal channel of the radio frequency receiving coil when the magnet rotates.
In one embodiment of the invention, the number of the radio frequency transmitting coils is at least two, and the radio frequency transmitting coils are arranged in parallel with each other.
In one embodiment of the invention, the radio frequency receiving coil is positioned between two adjacent radio frequency transmitting coils.
In one embodiment of the invention, the multi-channel coil has at least three or more channels.
In one embodiment of the invention, the multi-channel coil is in the form of an annular lap joint.
In one embodiment of the invention, the radio frequency receive coil is disposed on the center of the magnet.
In one embodiment of the invention, the number of turns of the radio frequency transmitting coil is greater than or equal to 1, and the line width is greater than or equal to 0.1 cm.
In one embodiment of the invention, the radio frequency transmitting coil has the number of turns of 2 and the line width of 2 cm.
In one embodiment of the present invention, the magnet is shaped in a four-column type.
Compared with the prior art, the technical scheme of the invention has the following advantages:
the radio frequency coil system applied to the rotating magnetic resonance is characterized in that the radio frequency transmitting coil is circular, the performance of the radio frequency transmitting coil is ensured, the radio frequency receiving coil is a multi-channel coil, the radio frequency shielding layers are positioned on two poles of the magnet, a fixed radio frequency environment can be provided for the radio frequency transmitting coil through the radio frequency shielding layers, a radio frequency field generated by the radio frequency transmitting coil can be more uniform, the signal amplification and control system is used for amplifying a magnetic resonance signal of the radio frequency receiving coil and providing a driving signal of the radio frequency receiving coil, a signal channel is selected for the radio frequency receiving coil when the magnet rotates, and the signal of the radio frequency receiving coil is optimized through a channel of the selective receiving coil in the rotating process of the magnet, so that the resonance frequency can be prevented from being shifted, therefore, the application problem of the radio frequency coil under the rotation condition is solved, and the application range of the radio frequency coil is wider.
Drawings
In order that the present disclosure may be more readily and clearly understood, reference is now made to the following detailed description of the embodiments of the present disclosure taken in conjunction with the accompanying drawings, in which
FIG. 1 is a schematic diagram of a radio frequency coil system of the present invention applied to rotating magnetic resonance;
FIG. 2 is another schematic view of the radio frequency coil assembly of the present invention;
fig. 3 is a schematic diagram of a multi-channel coil of the present invention.
The specification reference numbers indicate: 10-magnet, 11-radio frequency transmitting coil, 12-radio frequency receiving coil, 13-radio frequency shielding layer and 14-signal amplifying and controlling system.
Detailed Description
As shown in fig. 1 and fig. 2, the present embodiment provides a radio frequency coil system applied to rotational magnetic resonance, which includes a magnet 10, a power divider, a radio frequency transmitting coil 11, a radio frequency receiving coil 12, a radio frequency shielding layer 13, and a signal amplifying and controlling system 14, wherein the magnet 10 rotates around a center, the power divider is connected to the radio frequency transmitting coil 11, the radio frequency transmitting coil 11 and the radio frequency receiving coil 12 are both located in a rotation plane of the magnet 10, the radio frequency transmitting coil 11 is placed in a vertical direction of the rotation plane of the magnet 10, the radio frequency transmitting coil 11 is circular, the radio frequency receiving coil 12 is a multi-channel coil, the radio frequency shielding layer 13 is located on two poles of the magnet 10, the signal amplifying and controlling system 14 is configured to amplify a magnetic resonance signal of the radio frequency receiving coil 12, a drive signal for the radio frequency receive coil 12 is provided and the radio frequency receive coil 12 is signal channel selected as the magnet 10 rotates.
The radio frequency coil system applied to the rotating magnetic resonance in this embodiment includes a magnet 10, a power divider, a radio frequency transmitting coil 11, a radio frequency receiving coil 12, a radio frequency shielding layer 13, and a signal amplifying and controlling system 14, wherein the magnet 10 rotates around a center, the magnet 10 is used to provide a main magnetic field, the power divider is connected to the radio frequency transmitting coil 11, the power divider is used to convert a radio frequency signal and send the radio frequency signal to the radio frequency transmitting coil 11, when the magnetic resonance system images, the power divider is responsible for adjusting the radio frequency transmitting signal, converts the radio frequency transmitting signal into an analog radio frequency transmitting signal, sends the analog radio frequency transmitting signal to the radio frequency transmitting coil 11 through a radio frequency channel, and forms a radio frequency electromagnetic field by the radio frequency transmitting coil 11, the radio frequency transmitting coil 11 and the radio frequency receiving coil 12 are both located in a rotation plane of the magnet, the radio frequency transmitting coil 11 generates a radio frequency field required by magnetic resonance, the radio frequency transmitting coil 11 is placed in the vertical direction of the rotating plane of the magnet 10, the radio frequency receiving coil 13 receives a magnetic resonance signal, the radio frequency transmitting coil 11 is circular, the magnet 10 can rotate to any angle and is in a static state relative to a radio frequency environment, the performance of the radio frequency transmitting coil 11 is ensured, the radio frequency receiving coil 12 is a multi-channel coil, the radio frequency shielding layers 13 are positioned on two poles of the magnet 10, a fixed radio frequency environment can be provided for the radio frequency transmitting coil 11 through the radio frequency shielding layers 13, the radio frequency field generated by the radio frequency transmitting coil 11 can be more uniform, the signal amplifying and controlling system 14 is used for amplifying the magnetic resonance signal of the radio frequency receiving coil 12 and providing a driving signal of the radio frequency receiving coil 12, the signal channel selection is carried out on the radio frequency receiving coil 12 when the magnet 10 rotates, and the signal of the radio frequency receiving coil 13 is optimized through the channel of the selective receiving coil in the rotation process of the magnet 10, so that the purpose of optimizing the performance of the radio frequency receiving coil 13 is achieved, the resonance frequency can be prevented from being deviated, the application problem of the radio frequency coil under the rotation condition is solved, and the application range of the radio frequency coil is wider.
The number of the radio frequency transmitting coils 11 is at least two, and the radio frequency transmitting coils are arranged in parallel, so that the uniformity of radio frequency signals is guaranteed. The radio frequency receiving coil 12 is located between two adjacent radio frequency transmitting coils 11, so that the uniform transmission of signals is ensured. The radio frequency receiving coil 12 is placed in the center of the magnet 10, thereby advantageously ensuring efficient reception of the signal.
The multi-channel coil has at least three or more channels, thereby facilitating signal transmission by rotating the appropriate channel during rotation of the magnet 10. The multi-channel coil is in an annular lap joint mode, and is beneficial to eliminating the coupling between adjacent channels. In this embodiment, the multi-channel coil is eight channels, and the channels of the multi-channel coil are overlapped with each other to form a block, so that the coupling between the adjacent channels can be eliminated, and the section view and the distribution diagram of each channel are shown in fig. 3. During the rotation of the magnet 10, the radio frequency transmitting coil 11 is a circular coil, and the magnet 10 rotates to any angle, which is static relative to the radio frequency environment, whereas for the radio frequency receiving coil 12, there are some channels whose signals are weaker and disordered during the rotation of the magnet 10, which affects the signal-to-noise ratio, and thus it is necessary to shut off these channels. When the magnet 10 rotates, the signal amplification and control system 14 calculates the angle of the magnet 10, and simultaneously turns off the channels parallel to the magnet 10 according to the calculation result. As with the placement of magnet 10 described in fig. one, when the magnet is rotated-22.5 ° -22.5 °, CH1 and CH5 are turned off; when the magnet 10 rotates 22.5-67.5 degrees, the CH4 and CH8 paths are turned off; when the magnet 10 rotates 67.5-112.5 degrees, the CH3 and CH7 paths are turned off; when the magnet 10 rotates 112.5-157.5 degrees, the CH2 and CH6 paths are turned off. When the rotation is in the reverse direction, the channel switching is carried out at intervals of 45 degrees, so as to achieve the purpose of optimizing the received signal.
According to the feasibility of theoretical calculation and engineering application, the number of turns of the radio frequency transmitting coil 11 is more than or equal to 1, and the line width is more than or equal to 0.1 cm. The number of turns of the radio frequency transmitting coil is 2, when the line width is 2cm, a good radio frequency synthetic field uniform area can be obtained, and meanwhile, the conversion efficiency is very high. The magnet 10 is shaped as a four-pole type, facilitating rotation. The radio frequency shielding layer 13 is made of copper with good conductivity, so that the loss of the radio frequency transmitting coil 11 in a radio frequency environment can be reduced, and the efficiency of the radio frequency transmitting coil 11 can be improved.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.
Claims (9)
1. A radio frequency coil system for rotational magnetic resonance, characterized by: including magnet, power divider, radio frequency transmitting coil, radio frequency receiving coil, radio frequency shielding layer, signal amplification and control system, wherein the magnet is rotatory around the center, power divider with radio frequency transmitting coil links to each other, radio frequency transmitting coil and radio frequency receiving coil all is located in the rotation plane of magnet, just radio frequency transmitting coil puts in on the perpendicular direction of magnet rotation plane, radio frequency transmitting coil is circular, radio frequency receiving coil is the multichannel coil, radio frequency shielding layer is located on the two poles of magnet, signal amplification and control system are used for enlargiing radio frequency receiving coil's magnetic resonance signal provides radio frequency receiving coil's drive signal the magnet is rotatory when right radio frequency receiving coil carries out signal channel and selects.
2. A radio frequency coil system for rotary magnetic resonance as set forth in claim 1, wherein: the number of the radio frequency transmitting coils is at least two, and the radio frequency transmitting coils are arranged in parallel.
3. A radio frequency coil system for rotary magnetic resonance as set forth in claim 2, wherein: the radio frequency receiving coil is positioned between two adjacent radio frequency transmitting coils.
4. A radio frequency coil system for rotary magnetic resonance as set forth in claim 1, wherein: the multi-channel coil has at least three or more channels.
5. A radio frequency coil system for rotary magnetic resonance as set forth in claim 4, wherein: the multi-channel coil is in an annular lap joint mode.
6. A radio frequency coil system for rotary magnetic resonance as set forth in claim 1, wherein: the radio frequency receive coil is disposed on the center of the magnet.
7. A radio frequency coil system for rotary magnetic resonance as set forth in claim 1, wherein: the number of turns of the radio frequency transmitting coil is more than or equal to 1, and the line width is more than or equal to 0.1 cm.
8. A radio frequency coil system for rotary magnetic resonance as set forth in claim 7, wherein: the number of turns of the radio frequency transmitting coil is 2, and the line width is 2 cm.
9. A radio frequency coil system for rotary magnetic resonance as set forth in claim 1, wherein: the shape of the magnet is four-column type.
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CN201811640940.1A CN109738839B (en) | 2018-12-29 | 2018-12-29 | Radio frequency coil system applied to rotating magnetic resonance |
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CN201811640940.1A CN109738839B (en) | 2018-12-29 | 2018-12-29 | Radio frequency coil system applied to rotating magnetic resonance |
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CN109738839B true CN109738839B (en) | 2021-04-27 |
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CN109696642B (en) * | 2018-12-29 | 2024-06-04 | 佛山瑞加图医疗科技有限公司 | Radio frequency coil device and magnetic resonance imaging system |
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