Structure of a transmitting coil for a magnetic resonance imaging system

Abstract

The present invention relates to the field of magnetic resonance technology, and more specifically, to a structure for a transmitting coil for a magnetic resonance imaging system. The transmitting coil structure comprises a transmitting coil housing, characterized in that the housing comprises a plurality of through-holes, a printed circuit board is disposed within the transmitting coil housing, and a plurality of electronic components are disposed on the outer wall of the printed circuit board. The printed circuit board extends through the transmitting coil housing via the electronic components and is connected to the transmitting coil housing. Compared to the prior art, the structure of the transmitting coil is modified and the thickness of the transmitting coil is reduced, thereby reducing the room temperature aperture of the superconducting magnet, thereby reducing the size of the superconducting magnet and conserving superconducting wire, liquid helium, and steel.

Description

Technical Field

[0001] The present invention relates to the field of magnetic resonance technology, in particular to a structure of a transmitting coil for a magnetic resonance imaging system. Background Art

[0002] Magnetic resonance imaging (MRI) is an advanced, harmless medical imaging technique widely used in clinical medicine for the diagnosis of various human diseases and related scientific research. An MRI system primarily consists of a magnet, a gradient system (gradient coils and gradient amplifiers), a radio frequency link (RF transmitter coil, RF receiver coil, and RF amplifier), a spectrometer, and a computer. The most common MRI system currently consists of a superconducting magnet at the outermost layer, followed in descending order by the gradient coils, RF transmitter coil, and RF receiver coil. The transmitter coil, used to transmit the RF pulse signal to the patient, typically employs a birdcage structure due to its high RF field uniformity.

[0003] The magnet is the most important and costly component of an MRI system, and its geometry significantly impacts cost. Most horizontal-field superconducting magnets currently on the market typically have a room-temperature aperture of 850mm or 900mm. This space is used to accommodate gradient coils, radio frequency coils, and patient beds. Reducing the size of these components, and thus the room-temperature aperture of the magnet, could save significant amounts of superconducting wire, liquid helium, and steel, ultimately reducing the cost of the superconducting magnet. Summary of the Invention

[0004] To overcome the deficiencies of the prior art, the present invention provides a structure of a transmitting coil for a magnetic resonance imaging system. The structure of the transmitting coil is changed and the thickness of the transmitting coil is reduced, so that the room temperature aperture of the superconducting magnet can be reduced, thereby reducing the size of the superconducting magnet and saving the use of superconducting wire, liquid helium and steel.

[0005] To achieve the above objectives, a transmitting coil structure for a magnetic resonance imaging system is designed, comprising a transmitting coil housing. The structure is characterized in that: a plurality of through holes are provided in a shell wall of the transmitting coil housing; a printed circuit board is provided within the transmitting coil housing; a plurality of electronic components are provided on an outer wall of the printed circuit board; the printed circuit board extends through the transmitting coil housing via the electronic components and is connected to the transmitting coil housing.

[0006] The transmitting coil shell is a cylindrical structure.

[0007] The printed circuit board is a cylindrical structure.

[0008] The electronic components are one or more of block capacitors, inductors, and diodes.

[0009] The diameter of the printed circuit board is smaller than the inner diameter of the transmitting coil housing.

[0010] The transmitting coil shell is a non-metal shell that does not contain hydrogen elements.

[0011] A method for manufacturing a transmitting coil structure for a magnetic resonance imaging system, the specific method is as follows:

[0012] (1) According to the circuit layout of the printed circuit board, leave welding electrodes where electronic components such as block capacitors, inductors or diodes are needed;

[0013] (2) Place and fix the printed circuit board of the transmitting coil on the inner surface of the transmitting coil housing;

[0014] (3) Opening holes on the transmitting coil housing at locations where electronic components such as block capacitors, inductors, or diodes need to be exposed, according to the circuit layout of the printed circuit board;

[0015] (4) Solder the block capacitor, inductor or diode onto the printed circuit board.

[0016] Compared with the prior art, the present invention provides a transmitting coil structure for a magnetic resonance imaging system, which changes the structure of the transmitting coil and reduces the thickness of the transmitting coil. In this way, the room temperature aperture of the superconducting magnet can be reduced, thereby reducing the size of the superconducting magnet and saving the use of superconducting wire, liquid helium and steel.

[0017] The transmitting coil structure of the present invention allows the transmitting coil circuit to be further away from the gradient coil, thereby reducing the impact of the gradient coil shielding layer on the transmitting coil and improving transmission efficiency. It also allows the transmitting coil to be closer to the person or animal being scanned, facilitating the person or animal's absorption of radio frequency signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present invention.

[0019] See also Figure 1 , 1 is the transmitting coil housing, 2 is the printed circuit board, and 3 is the electronic components. DETAILED DESCRIPTION

[0020] The present invention will be further described below with reference to the accompanying drawings.

[0021] The traditional transmit coil for MRI is a long cylindrical structure. A flexible printed circuit board (PCB) encloses the outer surface of the mechanical plastic cylinder, housing discrete electronic components such as block capacitors, inductors, and diodes. To ensure the robustness of the transmit coil, the plastic casing is typically at least 4-6 mm thick. The thickness of the flexible PCB is 1 mm, while the block capacitors, inductors, and diodes are approximately 5-8 mm in the radial direction of the transmit coil. This brings the total radial thickness of the transmit coil to approximately 10-15 mm. Reducing the thickness of the transmit coil can also reduce the room-temperature aperture of the superconducting magnet, thereby lowering its cost. This transmit coil structure allows the transmit coil circuitry to be further away from the gradient coils, minimizing the impact of the gradient coil shielding on the transmit coil and improving transmission efficiency. It also allows the transmit coil to be closer to the person or animal being scanned, facilitating RF signal absorption.

[0022] like Figure 1 As shown, a plurality of through holes are provided on the shell wall of the transmitting coil housing 1, a printed circuit board 2 is provided inside the transmitting coil housing 1, and a plurality of electronic components 3 are provided on the outer wall of the printed circuit board 2. The printed circuit board 2 passes through the transmitting coil housing 1 through the electronic components 3 and is connected to the transmitting coil housing 1.

[0023] The transmitting coil housing 1 is a cylindrical structure.

[0024] The printed circuit board 2 has a cylindrical structure.

[0025] The electronic component 3 is one or more of a block capacitor, an inductor, and a diode.

[0026] The diameter of the printed circuit board 2 is smaller than the inner diameter of the transmitting coil housing 1 .

[0027] The transmitting coil housing 1 is a non-metallic housing that does not contain hydrogen elements.

[0028] One method for achieving the above-mentioned object is: soldering block capacitors, inductors, or diodes where needed according to the circuit layout of the printed circuit board; placing the printed circuit board of the transmitting coil on the inner surface of the transmitting coil housing; opening through holes on the transmitting coil housing where the block capacitors, inductors, or diodes need to be exposed according to the circuit layout of the printed circuit board; and soldering the block capacitors, inductors, or diodes on the printed circuit board.

[0029] The purpose of the present invention is to reduce the thickness of the transmitting coil so that the room temperature aperture of the superconducting magnet can be reduced, thereby reducing the size of the superconducting magnet and saving the use of superconducting wire, liquid helium and steel.

[0030] This structure can reduce the thickness of the transmitting coil while ensuring that the performance of the transmitting coil remains unchanged, thereby reducing the room temperature aperture of the magnet, reducing the size of the magnet, and reducing the cost of the magnet.

[0031] For some superconducting magnets with fixed apertures in the superconducting magnet chamber, such a structure can be used to use larger RF coils and receiving coils.

[0032] This structure allows the transmitting coil circuit to be located further away from the gradient coil, reducing the impact of the gradient coil shielding layer on the transmitting coil and improving transmission efficiency. It also allows the transmitting coil to be closer to the person or animal being scanned, facilitating their absorption of radio frequency signals.

[0033] Example 1:

[0034] A transmitting coil using this structure is used in a 1.5T MRI system. While the typical room-temperature aperture of a superconducting magnet is 850 mm, the radial thickness of a conventional transmitting coil is 15 mm. However, a transmitting coil using this structure can reduce this radial thickness to 10 mm without reducing the imaging area of ​​the entire MRI system. The room-temperature aperture of the superconducting magnet can be reduced to 840 mm. The entire magnet's superconducting coil structure, cryogenic cavity, and housing can be scaled down accordingly. Preliminary estimates suggest this structure can save 1,000 meters of superconducting wire and approximately 100 kilograms of steel.

[0035] Example 2:

[0036] A 7.0T small animal superconducting MRI system has a room-temperature aperture of 210 mm for the superconducting magnet and an inner diameter of 120 mm for the gradient coil. If a conventional transmitting coil (10 mm radial thickness) is used, the internal diameter of the transmitting coil is 100 mm. Such an MRI system can only scan small animals with a diameter less than 100 mm. However, using the transmitting coil of the present invention, the radial thickness can be reduced to 5 mm. The resulting usable internal space of the transmitting coil, 110 mm in diameter, is 10 mm larger than the imaging area of ​​a conventional transmitting coil, allowing for a wider range of small animals to be scanned. This allows for MRI scanning studies of small animals, such as rabbits, which were previously too large to fit within the RF coil.

Claims

1. A transmitting coil structure for a magnetic resonance imaging system, comprising a transmitting coil housing, characterized in that: A plurality of through holes are provided on the shell wall of the transmitting coil shell (1); a printed circuit board (2) is provided inside the transmitting coil shell (1); a plurality of electronic components (3) are provided on the outer wall of the printed circuit board (2); the printed circuit board (2) passes through the transmitting coil shell (1) through the electronic components (3) and is connected to the transmitting coil shell (1); The transmitting coil housing (1) is a cylindrical structure; The printed circuit board (2) is a cylindrical structure; The electronic components (3) are one or more of block capacitors, inductors, and diodes; The diameter of the printed circuit board (2) is smaller than the inner diameter of the transmitting coil housing (1); The transmitting coil housing (1) is a non-metallic housing that does not contain hydrogen elements; A method for manufacturing a transmitting coil structure for a magnetic resonance imaging system, the specific method is as follows: (1) According to the circuit layout of the printed circuit board, leave welding electrodes where the electronic components such as block capacitors, inductors or diodes need to be welded; (2) Place and fix the printed circuit board of the transmitting coil on the inner surface of the transmitting coil housing; (3) Opening a through hole on the transmitting coil housing at a location where the electronic components such as the block capacitor, inductor or diode need to be exposed according to the circuit layout of the printed circuit board; (4) Solder the block capacitor, inductor or diode onto the printed circuit board.

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