A distributed capacitance magnetic resonance radio frequency transmitting coil structure

Abstract

The present invention relates to the field of magnetic resonance technology, and specifically to a magnetic resonance radio frequency transmitting coil structure with distributed capacitance. A magnetic resonance radio frequency transmitting coil structure with distributed capacitance includes an insulating dielectric layer, and is characterized in that: the insulating dielectric layer is in a birdcage-like structure; a plurality of outer conductors are evenly distributed on the outer surface of the insulating dielectric layer, and a plurality of inner conductors are evenly distributed on the inner surface of the insulating dielectric layer; the outer conductors and the inner conductors are staggered and evenly distributed on the inner and outer surfaces of the insulating dielectric layer, and overlaps are provided between adjacent outer conductors and inner conductors. Compared with the prior art, a magnetic resonance radio frequency transmitting coil structure with distributed capacitance is provided, which can reduce the wall thickness of the transmitting coil, increase the inner diameter of the transmitting coil, improve patient comfort, have low cost, good image quality, high safety, and can significantly reduce the weight of the coil, improve its softness, and improve its reliability.

Description

Technical Field

[0001] The invention relates to the field of magnetic resonance technology, in particular to a magnetic resonance radio frequency transmitting coil structure with distributed capacitance. Background Art

[0002] Magnetic resonance imaging is an advanced technology for non-destructive imaging of the human body, which is widely used in the diagnosis of diseases in various parts of the human body. The MRI transmitting coil is an important component of the MRI system. Its performance directly determines the quality of MRI. The size of the inner diameter of the transmitting coil has a great influence on the size of the imaging area and the comfort of the patient. For clinical systems, the smaller the aperture, the more depressed the patient is, and the larger the aperture, the higher the patient comfort. For high-field strength and small-aperture scientific research MRI systems, the smaller the space, the fewer animals can be used for experiments, and the larger the space, the more animals can be used for experiments. The weight, process control, and cost control of the MRI transmitting coil are all very important.

[0003] like Figure 1 As shown, the traditional magnetic resonance radio frequency transmitting coil is composed of several lumped capacitors 1 (such as ceramic capacitors) and several segments of conductors 2, which are alternately arranged and connected in sequence to form a birdcage transmitting coil. These capacitors 1 and conductors 2 are usually attached to an insulating medium 3. This brings several problems: 1. The thickness of the capacitor 1 and the thickness of the plastic part that protects the capacitor 1 increase the thickness of the transmitting coil, thereby reducing the inner diameter of the transmitting coil. 2. The cost of the capacitor 1 used for the transmitting coil is relatively high. 3. The increase in the wall thickness of the transmitting coil leads to a decrease in the inner diameter of the coil. For clinical systems, the smaller the aperture, the more depressed the patient; for high-field strength and small-aperture scientific research magnetic resonance systems, the smaller the space, the smaller the animals that can be done, and the fewer experimental subjects the system faces. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, the present invention provides a distributed capacitance magnetic resonance radio frequency transmitting coil structure, which can reduce the wall thickness of the transmitting coil, increase the inner diameter of the transmitting coil, improve patient comfort, have low cost, good image quality, high safety, and can significantly reduce the weight of the coil, improve its softness, and improve its reliability.

[0005] To achieve the above purpose, a distributed capacitance magnetic resonance radio frequency transmitting coil structure is designed, comprising an insulating dielectric layer, characterized in that: the insulating dielectric layer is in a birdcage-like structure; a plurality of outer conductors are evenly distributed on the outer surface of the insulating dielectric layer, and a plurality of inner conductors are evenly distributed on the inner surface of the insulating dielectric layer; the outer conductors and the inner conductors are evenly distributed on the inner and outer surfaces of the insulating dielectric layer, and there is overlap between adjacent outer conductors and inner conductors.

[0006] The adjacent outer conductors, inner conductors and insulating medium layers form distributed capacitors, and a plurality of distributed capacitors are combined to form a radio frequency transmitting coil.

[0007] The outer conductor and the inner conductor are in an I-shaped structure, and two ends of adjacent outer conductors and inner conductors overlap.

[0008] The outer conductor and the inner conductor are of a T-shaped structure, and adjacent outer conductors are staggered and distributed on the outer surface of the insulating medium layer; adjacent inner conductors are staggered and distributed on the inner surface of the insulating medium layer; and the heads of adjacent outer conductors and inner conductors overlap.

[0009] The outer conductor, inner conductor and insulating medium layer are all made of double-sided printed circuit boards, the substrate of the printed circuit board is used as the insulating medium layer, and the outer copper layer and the inner copper layer form the outer conductor and the inner conductor.

[0010] The printed circuit board adopts a double-sided glass fiber epoxy resin circuit board, the substrate glass fiber epoxy resin of the printed circuit board is used as the insulating medium layer, and the outer copper layer and the inner copper layer form the outer conductor and the inner conductor.

[0011] The printed circuit board adopts a flexible polyimide double-sided circuit board, the substrate polyimide of the printed circuit board is used as an insulating medium layer, and the outer copper layer and the inner copper layer form an outer conductor and an inner conductor.

[0012] Compared with the prior art, the present invention provides a distributed capacitance magnetic resonance radio frequency transmitting coil structure, which can reduce the wall thickness of the transmitting coil, increase the inner diameter of the transmitting coil, improve patient comfort, have low cost, good image quality, high safety, and can significantly reduce the weight of the coil, improve its softness, and improve its reliability.

[0013] The magnetic resonance radio frequency transmitting coil structure of the present invention uses distributed capacitance to reduce the wall thickness of the transmitting coil, which can be closer to the gradient coil, thereby increasing the inner diameter of the transmitting coil of the magnetic resonance system, especially having great advantages in small-aperture high-field animal magnetic resonance systems.

[0014] The invention increases the aperture of the transmitting coil and improves the comfort of the patient; and increases the experimental range for the high-field strength and small-aperture scientific research magnetic resonance system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of a traditional magnetic resonance radio frequency transmitting coil.

[0016] Figure 2 It is a schematic diagram of the structure of the present invention.

[0017] Figure 3 It is a top view of the structure of the present invention.

[0018] Figure 4 It is a schematic structural diagram of another specific embodiment of the present invention.

[0019] Figure 5 for Figure 4 A partial schematic diagram of .

[0020] See also Figures 1 to 5 , 1 is the capacitor, 2 is the conductor, 3 is the insulating medium, 4 is the outer conductor, 5 is the inner conductor, and 6 is the insulating medium layer. DETAILED DESCRIPTION

[0021] The present invention will be further described below with reference to the accompanying drawings.

[0022] like Figures 2 to 5 As shown, the insulating dielectric layer 6 has a birdcage-like structure; a plurality of outer conductors 4 are evenly distributed on the outer surface of the insulating dielectric layer 6, and a plurality of inner conductors 5 are evenly distributed on the inner surface of the insulating dielectric layer 6; the outer conductors 4 and the inner conductors 5 are evenly distributed on the inner and outer surfaces of the insulating dielectric layer 6 in an alternating manner, and adjacent outer conductors 4 and inner conductors 5 overlap.

[0023] The adjacent outer conductor 4, inner conductor 5 and insulating medium layer 6 form a distributed capacitor, and a plurality of distributed capacitors are combined to form a radio frequency transmitting coil.

[0024] The outer conductor 4 and the inner conductor 5 are in an I-shaped structure, and two ends of adjacent outer conductors 4 and inner conductors 5 overlap.

[0025] The outer conductor 4 and the inner conductor 5 are of a "T"-shaped structure, and adjacent outer conductors 4 are staggered on the outer surface of the insulating dielectric layer 6; adjacent inner conductors 5 are staggered on the inner surface of the insulating dielectric layer 6; and the heads of adjacent outer conductors 4 and inner conductors 5 overlap.

[0026] The outer conductor 4, the inner conductor 5 and the insulating dielectric layer 6 all adopt a double-sided printed circuit board, the substrate of the printed circuit board is used as the insulating dielectric layer 6, and the outer conductor 4 and the inner conductor 5 are formed by the outer copper cladding and the inner copper cladding.

[0027] The printed circuit board adopts a double-sided glass fiber epoxy resin circuit board, the substrate glass fiber epoxy resin of the printed circuit board is used as the insulating medium layer 6, the outer copper layer and the inner copper layer form the outer conductor 4 and the inner conductor 5.

[0028] The printed circuit board adopts a flexible polyimide double-sided circuit board, the substrate polyimide of the printed circuit board is used as an insulating dielectric layer 6, and the outer copper layer and the inner copper layer form an outer conductor 4 and an inner conductor 5.

[0029] Embodiment 1 of the invention, as Figure 2 , Figure 3 As shown, the birdcage-shaped transmitting coil has 16 distributed capacitors at each end, a total of 32 distributed capacitors, no ceramic capacitors, and the insulating dielectric layer 6 is a 50um thick FR4 substrate.

[0030] The outer conductor 4 and the inner conductor 5 are both in the shape of an I, and are evenly distributed on the birdcage-shaped insulating dielectric layer 6. There are 8 outer conductors 4 and 8 inner conductors 5, which are alternately located on the inner and outer surfaces of the birdcage-shaped insulating dielectric layer 6, respectively, forming 16 distributed capacitors at both ends of the birdcage.

[0031] Embodiment 2 of the invention, as Figure 4 , Figure 5 As shown, the birdcage-shaped transmitting coil has 16 distributed capacitors at each end and 16 distributed capacitors in the middle of the birdcage, a total of 48 distributed capacitors, without any ceramic capacitors, and the insulating dielectric layer 6 is 50um thick polyimide.

[0032] The outer conductor 4 and the inner conductor 5 are both "T" shaped and evenly distributed on the birdcage-shaped insulating dielectric layer 6. There are 16 outer conductors 4 (8 at each end) and 16 inner conductors 5 (8 at each end), which are staggered on the inner and outer surfaces of the birdcage-shaped insulating dielectric layer 6, forming 16 distributed capacitors at both ends of the birdcage. The outer conductor 4 at one end and the inner conductor 5 at the other end overlap in the middle of the birdcage to form a distributed capacitor, with a total of 16 distributed capacitors.

[0033] The conductors of the inductor and distributed capacitor in the magnetic resonance radio frequency transmitting coil structure of the present invention can also be in other shapes, or the substrate of other printed circuit boards can be used as the insulating dielectric layer. The same idea can be used to easily manufacture radio frequency transmitting coil structures of different sizes, shapes and operating frequencies.

[0034] Therefore, the present invention uses a number of conductors that are not connected to each other, but the conductors are no longer connected by independent lumped ceramic capacitors, but these conductors are used to form distributed capacitors. These conductors form inductances on the one hand, and also participate in the formation of distributed capacitors at the same time. The resonant frequency can be adjusted by adjusting the length, width, relative position, etc. of these conductors. When the resonant frequency is equal to the frequency of the magnetic resonance signal, the radio frequency signal can be effectively transmitted and the magnetic resonance radio frequency signal can be detected.

[0035] Therefore, the structure of the present invention does not need to use ceramic capacitors, reduces the thickness of the transmitting coil, increases the inner diameter of the transmitting coil, has a simple production process, low cost, and convenient debugging, and can significantly reduce the weight of the flexible coil, increase its softness, and improve its reliability.

[0036] In summary, the structure of the present invention reduces the wall thickness of the transmitting coil and can be closer to the gradient coil, thereby increasing the inner diameter of the transmitting coil of the magnetic resonance system, which has great advantages in small-aperture high-field animal magnetic resonance systems. The present invention increases the aperture of the transmitting coil and improves the comfort of the patient; for high-field strength small-aperture scientific research magnetic resonance systems, the experimental range is increased. The magnetic resonance radio frequency transmitting coil structure using distributed capacitance of the present invention has low cost, good image quality, high safety, and can significantly reduce the weight of the coil, improve its softness, and improve its reliability. It has a clever design, a simple structure, and a simple production process, and is suitable for large-scale promotion and application.

Claims

1. A distributed capacitance magnetic resonance radio frequency transmitting coil structure, comprising an insulating dielectric layer, characterized in that: The insulating dielectric layer (6) has a birdcage-like structure; a plurality of outer conductors (4) are evenly distributed on the outer surface of the insulating dielectric layer (6), and a plurality of inner conductors (5) are evenly distributed on the inner surface of the insulating dielectric layer (6); the outer conductors (4) and the inner conductors (5) are evenly distributed on the inner and outer surfaces of the insulating dielectric layer (6), and adjacent outer conductors (4) and inner conductors (5) overlap; The outer conductor (4), inner conductor (5) and insulating dielectric layer (6) are all made of a double-sided printed circuit board, the substrate of the printed circuit board is used as the insulating dielectric layer (6), and the outer copper layer and the inner copper layer form the outer conductor (4) and the inner conductor (5); The outer conductor (4) and the inner conductor (5) are of an "I"-shaped structure, and the two ends of adjacent outer conductors (4) and inner conductors (5) overlap; Alternatively, the outer conductor (4) and the inner conductor (5) are of a "T"-shaped structure, and adjacent outer conductors (4) are arranged in an interlaced manner on the outer surface of the insulating dielectric layer (6); adjacent inner conductors (5) are arranged in an interlaced manner on the inner surface of the insulating dielectric layer (6); and the heads of adjacent outer conductors (4) and inner conductors (5) overlap.

2. The magnetic resonance radio frequency transmitting coil structure with distributed capacitance according to claim 1, characterized in that: The adjacent outer conductor (4), inner conductor (5) and insulating medium layer (6) form a distributed capacitor, and a plurality of distributed capacitors are combined to form a radio frequency transmitting coil.

3. The magnetic resonance radio frequency transmitting coil structure with distributed capacitance according to claim 1, characterized in that: The printed circuit board adopts a double-sided glass fiber epoxy resin circuit board, the substrate glass fiber epoxy resin of the printed circuit board is used as an insulating medium layer (6), and the outer copper layer and the inner copper layer form an outer conductor (4) and an inner conductor (5).

4. The magnetic resonance radio frequency transmitting coil structure with distributed capacitance according to claim 1, characterized in that: The printed circuit board adopts a flexible polyimide double-sided circuit board, the substrate polyimide of the printed circuit board is used as an insulating dielectric layer (6), and the outer copper layer and the inner copper layer form an outer conductor (4) and an inner conductor (5).

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