Transmit-receive system in a vertical field magnetic resonance imaging system

Abstract

The application provides a transmitting-receiving system in a vertical field magnetic resonance imaging system, wherein the transmitting-receiving system comprises a transmitting-receiving body coil, a coil shell and a transmitting-receiving switch circuit; the transmitting-receiving body coil comprises a solenoid channel coil and a saddle channel coil; the solenoid channel coil and the saddle channel coil are respectively wrapped outside the coil shell; the transmitting-receiving body coil is used for transmitting radio frequency pulses to a human body examination site and collecting magnetic resonance signals of the human body examination site; and the transmitting-receiving switch circuit is used for controlling the transmitting-receiving body coil to transmit radio frequency pulses or collect magnetic resonance signals. Through the scheme, the requirement of system radio frequency power can be reduced.

Description

Technical Field

[0001] This application relates to the field of magnetic resonance imaging technology, and in particular to a transmit and receive system in a vertical field magnetic resonance imaging system. Background Technology

[0002] In existing technologies, vertical-field magnetic resonance imaging (VMRI) systems consist of independent transmitting and receiving coils. The transmitting coil, used to emit electromagnetic waves to establish a radio frequency magnetic field to excite human tissue, is called the transmitting coil, while the receiving coil, used to acquire magnetic resonance signals, is called the receiving coil. In existing VMRI systems, the transmitting coil is often a planar transmitting coil, mounted on the surface of a gradient coil inside a magnet. Between the transmitting and gradient coils, there is a radio frequency shielding layer to reduce the influence of the gradient coil and the magnet on the transmitting coil. Planar transmitting coils require a relatively large radio frequency transmitting coil to excite a uniform radio frequency field at the imaging center, and a larger radio frequency coil requires more radio frequency power. Furthermore, due to the spatial limitations of VMRI, the transmitting coil needs to be as thin as possible. Because the entire radio frequency coil wiring is very close to the radio frequency shielding layer, a large portion of the radio frequency energy emitted by the transmitting coil is lost in the shielding layer. This further increases the radio frequency power required for the magnetic resonance imaging system to excite hydrogen protons; typically, a planar transmitting coil requires 6 kW of radio frequency power for applications with a field strength of 0.3T-0.5T. Moving the transmitting coil and radio frequency shielding away from each other would compress the imaging space. To ensure the size of the imaging space, the distance between the two pole disks of the magnet would be increased, resulting in a decrease in magnetic field strength. To maintain the same magnetic field strength, more magnetic material would be needed, increasing the overall cost of the system. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide a transmit and receive system in a vertical field magnetic resonance imaging system to ensure the patient imaging space size, reduce the system radio frequency power requirements, and thus reduce the overall system cost.

[0004] In a first aspect, embodiments of this application provide a transmit-receive system in a vertical field magnetic resonance imaging system, wherein the transmit-receive system includes: a transmit-receive coil, a coil housing, and a transmit-receive switch circuit; the transmit-receive coil includes a solenoid channel coil and a saddle-shaped channel coil; the solenoid channel coil and the saddle-shaped channel coil are respectively wrapped around the outside of the coil housing;

[0005] The transmitting and receiving coil is used to transmit the radio frequency pulse to the human body examination site and to collect the magnetic resonance signal of the human body examination site.

[0006] The transceiver switch circuit is used to control the transmitting and receiving coils to transmit the radio frequency pulses or acquire the magnetic resonance signals.

[0007] In conjunction with the first aspect, this application provides a first possible implementation of the first aspect, wherein the solenoid channel coil is a closed coil composed of a first semi-enclosed wire, a second semi-enclosed wire, a first connecting wire, and a second connecting wire; wherein the first semi-enclosed wire and the second semi-enclosed wire are respectively wrapped around the coil housing, and the first semi-enclosed wire and the second semi-enclosed wire are cross-connected by the first connecting wire and the second connecting wire.

[0008] In conjunction with the first possible implementation of the first aspect, this application provides a second possible implementation of the first aspect, wherein the saddle-shaped channel coil is a closed coil, including a first coil group and a second coil group; the first coil group and the second coil group are symmetrically wrapped around the coil housing.

[0009] In conjunction with the second possible implementation of the first aspect, this application provides a third possible implementation of the first aspect, wherein the first coil group includes a first bow-shaped conductor, a third bow-shaped conductor, a third connecting conductor, and a sixth connecting conductor, and one end of the first bow-shaped conductor is connected to one end of the third bow-shaped conductor through the third connecting conductor;

[0010] The second coil group includes a second bow-shaped conductor, a fourth bow-shaped conductor, a fourth connecting conductor, and a fifth connecting conductor, wherein one end of the second bow-shaped conductor is connected to one end of the fourth bow-shaped conductor through the fourth connecting conductor;

[0011] The other end of the first bow-shaped conductor is connected to the other end of the fourth bow-shaped conductor via the fifth connecting conductor; the other end of the second bow-shaped conductor is connected to the other end of the third bow-shaped conductor via the sixth connecting conductor.

[0012] The first and second bow-shaped conductors are located on the same plane; the third and fourth bow-shaped conductors are located on the same plane.

[0013] In conjunction with the first aspect, this application provides a fourth possible implementation of the first aspect, wherein the transceiver switch circuit is respectively connected to the solenoid channel coil and the saddle-shaped channel coil;

[0014] The transceiver switch circuit is used to send the received radio frequency pulse to the solenoid channel coil and the saddle channel coil when a high-level signal is received from an external source; and to receive the magnetic resonance signal collected by the solenoid channel coil and the saddle channel coil when a low-level signal is received from an external source.

[0015] In conjunction with the first aspect, this application provides a fifth possible implementation of the first aspect, wherein the transmitting-receiving coil is used to transmit the radio frequency pulse to the human body examination site when it receives the radio frequency pulse transmitted by the transceiver switch circuit; and when the transceiver switch circuit receives a low-level signal, the transmitting-receiving coil collects the magnetic resonance signal of the human body examination site and sends the magnetic resonance signal to the transceiver switch circuit.

[0016] In conjunction with the third possible implementation of the first aspect, this application provides a sixth possible implementation of the first aspect, wherein the first semi-enclosed conductor and the second semi-enclosed conductor are located between the plane containing the first bow-shaped conductor and the second bow-shaped conductor and the plane containing the third bow-shaped conductor and the fourth bow-shaped conductor; the first semi-enclosed conductor intersects the third connecting conductor at a first intersection point, the fourth connecting conductor at a second intersection point, the fifth connecting conductor at a third intersection point, and the sixth connecting conductor at a fourth intersection point; the second semi-enclosed conductor intersects the third connecting conductor at a fifth intersection point, the fourth connecting conductor at a sixth intersection point, the fifth connecting conductor at a seventh intersection point, and the sixth connecting conductor at an eighth intersection point.

[0017] In conjunction with the sixth possible implementation of the first aspect, this application provides a seventh possible implementation of the first aspect, wherein, at the first intersection, the first semi-enclosed wire is between the third connecting wire and the coil housing; at the second intersection, the first semi-enclosed wire is between the fourth connecting wire and the coil housing; at the third intersection, the fifth connecting wire is between the first semi-enclosed wire and the coil housing; at the fourth intersection, the sixth connecting wire is between the first semi-enclosed wire and the coil housing; at the fifth intersection, the second semi-enclosed wire is between the third connecting wire and the coil housing; at the sixth intersection, the second semi-enclosed wire is between the fourth connecting wire and the coil housing; at the seventh intersection, the fifth connecting wire is between the second semi-enclosed wire and the coil housing; and at the eighth intersection, the sixth connecting wire is between the second semi-enclosed wire and the coil housing.

[0018] In conjunction with the fourth possible implementation of the first aspect, this application provides an eighth possible implementation of the first aspect, wherein the transceiver switching circuit includes: a 90-degree bridge, a first quarter-wavelength line, a second quarter-wavelength line, a first diode, a second diode, a third diode, a fourth diode, a first isolation absorption resistor, a second isolation absorption resistor, and a low-noise amplifier;

[0019] The 90-degree bridge is connected to the solenoid channel coil, the saddle-shaped channel coil, the first quarter-wavelength line, the second quarter-wavelength line, the negative terminal of the second diode, and the positive terminal of the third diode, respectively. The first quarter-wavelength line is connected to the 90-degree bridge, the negative terminal of the second diode, the positive terminal of the first diode, and the first isolation absorption resistor, respectively. The first isolation absorption resistor is connected to the first quarter-wavelength line, the positive terminal of the first diode, and the ground electrode, respectively. The negative terminal of the first diode is connected to the ground electrode. The positive terminal of the second diode is connected to the transmitter, and the negative terminal of the second diode is connected to the first quarter-wavelength line and the 90-degree bridge, respectively.

[0020] The second quarter-wavelength line is connected to the 90-degree bridge, the positive terminal of the third diode, the positive terminal of the fourth diode, and the low-noise amplifier, respectively; the low-noise amplifier is connected to the positive terminal of the fourth diode, the second quarter-wavelength line, and the receiving end, respectively; the second isolation absorption resistor is connected to the negative terminal of the third diode and the ground electrode, respectively; the fourth diode is connected to the second quarter-wavelength line, the low-noise amplifier, and the ground electrode, respectively.

[0021] The transceiver switching circuit is specifically configured such that when the high-level signal is received, the first diode, the second diode, the third diode, and the fourth diode are turned on, and one end of the first quarter-wavelength line is short-circuited while the other end is open-circuited, so that the received radio frequency pulse is transmitted to the solenoid channel coil and the saddle channel coil through the second diode and the 90-degree bridge; and when the low-level signal is received, the first diode, the second diode, the third diode, and the fourth diode are not turned on, and the magnetic resonance signal collected by the solenoid channel coil and the saddle channel coil is transmitted to the low-noise amplifier through the 90-degree bridge and the second quarter-wavelength line, and the magnetic resonance signal is amplified by the low-noise amplifier, so that the amplified magnetic resonance signal is sent to the receiving end.

[0022] In conjunction with the first aspect, this application provides a ninth possible implementation of the first aspect, wherein a designated receiving coil is further included; the designated receiving coil is disposed within the coil housing;

[0023] The designated receiving coil is used to acquire the magnetic resonance signal of the human body examination site when the transmitting receiving coil is used as a transmitting coil and transmits the radio frequency pulse to the human body examination site.

[0024] This application provides a transmit-receive system in a vertical field magnetic resonance imaging system. Firstly, when scanning the patient's body, the operating state of the transmit-receive coil is switched via a transmit / receive switch circuit, allowing the coil to function as both a transmit and receive coil. Furthermore, the distribution of the transmit-receive coil's wiring ensures that the electromagnetic field generated by this wiring is concentrated within the volume of the wiring. Compared to traditional planar transmit coils, the transmit-receive coil couples less electromagnetic field onto the RF shielding layer, resulting in less RF power loss. This means that even when the transmit-receive coil is close to the RF shielding layer, there is no significant loss of RF field strength at the imaging center. This only requires meeting the thickness requirements of the coil's outer shell frame, avoiding excessive loss of vertical space due to excessive coil thickness. Therefore, this solution helps ensure sufficient imaging space for the patient, reduces the system's RF power requirements, and thus lowers the overall system cost.

[0025] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A schematic diagram of the structure of the transmitter-receiver coil provided in an embodiment of this application is shown;

[0028] Figure 2 A schematic diagram of the capacitor on the transmitting and receiving coil provided in an embodiment of this application is shown;

[0029] Figure 3 A schematic diagram of the structure of the solenoid channel coil provided in the embodiment of this application is shown;

[0030] Figure 4 A schematic diagram of the saddle-shaped channel coil provided in an embodiment of this application is shown;

[0031] Figure 5 A schematic diagram of the transceiver switch circuit provided in an embodiment of this application is shown;

[0032] Figure 6 A schematic diagram of the structure of a designated receiving coil provided in an embodiment of this application is shown. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0034] Considering the high RF power and overall cost of the RF transmitting coil in the prior art, this application provides a transmitting and receiving system in a vertical field magnetic resonance imaging system, which will be described below through embodiments.

[0035] To facilitate understanding of this embodiment, a detailed description of the transmit and receive system in a vertical field magnetic resonance imaging system disclosed in this application embodiment will be provided first. Figure 1 A schematic diagram of the structure of the transmitter-receiver coil provided in an embodiment of this application is shown, as follows: Figure 1 As shown, the transmitting and receiving system includes: a transmitting and receiving coil, a coil housing, and a transmitting and receiving switch circuit; the transmitting and receiving coil includes a solenoid channel coil and a saddle-shaped channel coil; the solenoid channel coil and the saddle-shaped channel coil are respectively wrapped around the outside of the coil housing;

[0036] The transmitter-receiver coil is used to transmit radio frequency pulses to the human body being examined and to collect magnetic resonance signals from the human body being examined.

[0037] The transceiver switch circuit is used to control the transmitting and receiving coils to transmit radio frequency pulses or acquire magnetic resonance signals.

[0038] In this embodiment, the transmit-receive system is applied to a vertical field magnetic resonance imaging (MRI) system. The transmit-receive coil in this system can be used as both the transmit and receive coils for the MRI system. In the MRI system, the transmit coil emits radio frequency pulses towards the examined area of ​​the human body to excite hydrogen protons. The hydrogen protons at the examined area absorb energy and deflect and spin in one direction. After the radio frequency pulse stops, nuclear magnetic relaxation begins; this process of hydrogen proton recovery is called the relaxation process, and the time required to return to the original equilibrium state is called the relaxation time. During relaxation, the hydrogen protons release the absorbed energy and return to the equilibrium state. The released electromagnetic energy is converted into a magnetic resonance signal, which is then acquired by the receive coil and used for imaging. The examined areas of the human body include, but are not limited to, the head, abdomen, and joints.

[0039] In this embodiment, the transmitter-receiver coil switches between transmitting and receiving coils under the control of the transceiver switching circuit. When the transmitter-receiver coil receives an RF pulse from the transceiver switching circuit, it functions as a transmitter coil, emitting RF pulses towards the examined area of ​​the human body. When the transceiver switching circuit receives a low-level signal, the transmitter-receiver coil functions as a receiver coil, acquiring magnetic resonance signals from the examined area of ​​the human body.

[0040] The transmitter-receiver coil is wound around a coil housing and connected to a transceiver switching circuit. Specifically, the transmitter-receiver coil includes a solenoid channel coil and a saddle-shaped channel coil, which are wound around the coil housing and connected to the transceiver switching circuit respectively.

[0041] In one possible implementation, such as Figure 1 As shown, the solenoid channel coil is a closed coil composed of a first semi-enclosed wire 1, a second semi-enclosed wire 2, a first connecting wire 3, and a second connecting wire 4; wherein, the first semi-enclosed wire 1 and the second semi-enclosed wire 2 are respectively wrapped around the coil shell, and the first semi-enclosed wire 1 and the second semi-enclosed wire 2 are cross-connected by the first connecting wire 3 and the second connecting wire 4.

[0042] In one possible implementation, the saddle-shaped channel coil is a closed coil, including a first coil group and a second coil group; the first coil group and the second coil group are symmetrically wrapped around the coil shell.

[0043] like Figure 1As shown, the first coil group includes a first bow-shaped wire 5, a third bow-shaped wire 7, a third connecting wire 9, and a sixth connecting wire 12. One end of the first bow-shaped wire 5 is connected to one end of the third bow-shaped wire 7 through the third connecting wire 9.

[0044] The second coil group includes a second bow-shaped conductor 6, a fourth bow-shaped conductor 8, a fourth connecting conductor 10, and a fifth connecting conductor 11. One end of the second bow-shaped conductor 6 is connected to one end of the fourth bow-shaped conductor 8 through the fourth connecting conductor 10.

[0045] The other end of the first bow-shaped conductor 5 is connected to the other end of the fourth bow-shaped conductor 8 via the fifth connecting conductor 11; the other end of the second bow-shaped conductor 6 is connected to the other end of the third bow-shaped conductor 7 via the sixth connecting conductor 12;

[0046] The first bow-shaped conductor 5 and the second bow-shaped conductor 6 are located on the same plane; the third bow-shaped conductor 7 and the fourth bow-shaped conductor 8 are located on the same plane.

[0047] Figure 2 A schematic diagram of the capacitor on the transmitter / receiver coil provided in an embodiment of this application is shown, as follows. Figure 2 As shown, four capacitors are connected in series on the solenoid channel coil, located on the first semi-enclosed wire 1 and the second semi-enclosed wire 2 respectively. Two capacitors are located on the first semi-enclosed wire 1, and two capacitors are located on the second semi-enclosed wire 2. Four capacitors are connected in series on the saddle-shaped channel coil, with one capacitor each on the third connecting wire 9, the fourth connecting wire 10, the fifth connecting wire 11, and the sixth connecting wire 12. In this embodiment, since the transmitter-receiver coil is a combined transmitter-receiver coil, a detuning circuit is not required in the transmitter-receiver coil circuit.

[0048] To facilitate a clear understanding of the structure of the solenoid channel coil and the saddle-shaped channel coil in this embodiment, Figure 3 A schematic diagram of the structure of the solenoid channel coil provided in the embodiment of this application is shown; Figure 4 A schematic diagram of the saddle-shaped channel coil provided in an embodiment of this application is shown.

[0049] In this embodiment, the design of the transmitter-receiver coil can generate a uniform circular polarization field, which can also improve the transmission efficiency of the transmitter-receiver coil when it is used as a transmitter coil. Conversely, it can also improve the signal-to-noise ratio of the transmitter-receiver coil when it is used as a receiver coil for imaging.

[0050] In one possible implementation, the transceiver switch circuit is connected to the solenoid channel coil and the saddle channel coil, respectively;

[0051] The transceiver switch circuit is used to send the received radio frequency pulse to the solenoid channel coil and the saddle channel coil when a high-level signal is received from an external source; and to receive the magnetic resonance signal collected by the solenoid channel coil and the saddle channel coil when a low-level signal is received from an external source.

[0052] The transmitter-receiver coil is used to transmit radio frequency pulses to the human body examination site when it receives radio frequency pulses sent by the transceiver switching circuit; and to collect magnetic resonance signals of the human body examination site when the transceiver switching circuit receives a low-level signal, and send the magnetic resonance signals to the transceiver switching circuit.

[0053] Here, a high-level signal refers to a signal where the bias signal is high, and a low-level signal refers to a signal where the bias signal is low.

[0054] In one possible implementation, such as Figure 1 As shown, the first semi-encircling conductor 1 and the second semi-encircling conductor 2 are located between the plane containing the first bow-shaped conductor 5 and the second bow-shaped conductor 6, and the plane containing the third bow-shaped conductor 7 and the fourth bow-shaped conductor 8. The first semi-encircling conductor 1 intersects the third connecting conductor 9 at the first intersection point, the fourth connecting conductor 10 at the second intersection point, the fifth connecting conductor 11 at the third intersection point, and the sixth connecting conductor 12 at the fourth intersection point. The second semi-encircling conductor 2 intersects the third connecting conductor 9 at the fifth intersection point, the fourth connecting conductor 10 at the sixth intersection point, the fifth connecting conductor 11 at the seventh intersection point, and the sixth connecting conductor 12 at the eighth intersection point. The third connecting conductor 9 is parallel to the fourth connecting conductor 10.

[0055] In one possible implementation, such as Figure 1 As shown, at the first intersection, the first semi-enclosed wire 1 is between the third connecting wire 9 and the coil housing; at the second intersection, the first semi-enclosed wire 1 is between the fourth connecting wire 10 and the coil housing; at the third intersection, the fifth connecting wire 11 is between the first semi-enclosed wire 1 and the coil housing; at the fourth intersection, the sixth connecting wire 12 is between the first semi-enclosed wire 1 and the coil housing; at the fifth intersection, the second semi-enclosed wire 2 is between the third connecting wire 9 and the coil housing; at the sixth intersection, the second semi-enclosed wire 2 is between the fourth connecting wire 10 and the coil housing; at the seventh intersection, the fifth connecting wire 11 is between the second semi-enclosed wire 2 and the coil housing; and at the eighth intersection, the sixth connecting wire 12 is between the second semi-enclosed wire 2 and the coil housing.

[0056] In one possible implementation, Figure 5 A schematic diagram of the transceiver switch circuit provided in an embodiment of this application is shown, as follows: Figure 5As shown, the transceiver switch circuit includes: a 90-degree bridge 13, a first quarter-wavelength line 14, a second quarter-wavelength line 15, a first diode 16, a second diode 17, a third diode 18, a fourth diode 19, a first isolation absorption resistor 20, a second isolation absorption resistor 21, and a low-noise amplifier 22.

[0057] The 90-degree bridge 13 is connected to the solenoid channel coil 25, the saddle-shaped channel coil 26, the first quarter-wavelength line 14, the second quarter-wavelength line 15, the negative terminal of the second diode 17, and the positive terminal of the third diode 18, respectively. The first quarter-wavelength line 14 is connected to the 90-degree bridge 13, the negative terminal of the second diode 17, the positive terminal of the first diode 16, and the first isolation absorption resistor 20, respectively. The first isolation absorption resistor 20 is connected to the first quarter-wavelength line 14, the positive terminal of the first diode 16, and the ground electrode, respectively. The negative terminal of the first diode 16 is connected to the ground electrode. The positive terminal of the second diode 17 is connected to... Connecting to transmitter 23, the cathode of second diode 17 is connected to first quarter-wavelength line 14 and 90-degree bridge 13 respectively; second quarter-wavelength line 15 is connected to 90-degree bridge 13, the anode of third diode 18, the anode of fourth diode 19 and low-noise amplifier 22 respectively; low-noise amplifier 22 is connected to the anode of fourth diode 19, second quarter-wavelength line 15 and receiver 24 respectively; second isolation absorption resistor 21 is connected to the cathode of third diode 18 and ground electrode respectively; fourth diode 19 is connected to second quarter-wavelength line 15, low-noise amplifier 22 and ground electrode respectively.

[0058] The transceiver switching circuit is specifically configured such that when a high-level signal is received, the first diode 16, the second diode 17, the third diode 18, and the fourth diode 19 are turned on, and one end of the first quarter-wavelength line 14 is short-circuited while the other end is open-circuited, so that the received radio frequency pulse is transmitted to the solenoid channel coil and the saddle channel coil through the second diode 17 and the 90-degree bridge 13; and when a low-level signal is received, the first diode 16, the second diode 17, the third diode 18, and the fourth diode 19 are not turned on, and the magnetic resonance signal collected by the solenoid channel coil and the saddle channel coil is transmitted to the low-noise amplifier 22 through the 90-degree bridge 13 and the second quarter-wavelength line 15, and the magnetic resonance signal is amplified by the low-noise amplifier 22, so that the amplified magnetic resonance signal is sent to the receiver 24. The transmitter 23 is used to send radio frequency pulses to the transceiver switching circuit, and the receiver 24 is used to receive the amplified magnetic resonance signal from the transceiver switching circuit.

[0059] In this embodiment, due to the characteristics of the quarter-wavelength line, when the transceiver switching circuit receives the high-level signal, one end of the first quarter-wavelength line 14 is short-circuited, and the RF pulse is equivalent to an open circuit at the other end of the first quarter-wavelength line 14. Therefore, the RF pulse will not pass through the first quarter-wavelength line 14 and will be directly fed into the solenoid channel coil and the saddle channel coil. Since the phase difference between the transmitter and receiver coils is 90 degrees, a 90-degree bridge 13 is used in this embodiment. When the transmitter and receiver coil acts as the receiver coil to receive the magnetic resonance signal, the acquired magnetic resonance signal is very weak. At this time, the diode in the transceiver switching circuit is not conducting, and the magnetic resonance signal is synthesized through the second quarter-wavelength line 15 and output to the low-noise amplifier.

[0060] In one possible implementation, the transmitter and receiver coils are made of copper. Specifically, the solenoid channel coil and the saddle channel coil are made of copper.

[0061] In one possible implementation, Figure 6 A schematic diagram of the structure of a specified receiving coil provided in an embodiment of this application is shown, as follows: Figure 6 As shown, the transmitting and receiving system also includes: a designated receiving coil 27; the designated receiving coil 27 is disposed inside the coil housing;

[0062] The designated receiving coil 27 is used to acquire the magnetic resonance signal of the human body examination site when the transmitting and receiving coil is used as a transmitting coil and transmits radio frequency pulses to the human body examination site.

[0063] In this embodiment, different receiving coils are suitable for different human body examination sites. In order to better acquire magnetic resonance signals from different human body examination sites, the transmitting and receiving coil can be used only as a transmitting coil in this embodiment. At this time, a designated receiving coil 27 is set in the transmitting and receiving coil, wherein the model of the designated receiving coil is determined according to the human body examination site.

[0064] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0065] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0066] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0067] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The scope of protection of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of protection of the claims.

Claims

1. A transmit and receive system in a vertical field magnetic resonance imaging system, characterized in that, The transmitting and receiving system includes: a transmitting and receiving coil, a coil housing, and a transmitting and receiving switch circuit; the transmitting and receiving coil includes a solenoid channel coil and a saddle-shaped channel coil; the solenoid channel coil and the saddle-shaped channel coil are respectively wrapped around the outside of the coil housing; The transmitting and receiving coil is used to transmit radio frequency pulses to the human body examination site and to collect magnetic resonance signals from the human body examination site. The transceiver switch circuit is used to control the transmitting and receiving coil to transmit the radio frequency pulse or to acquire the magnetic resonance signal; The transceiver switch circuit is connected to the solenoid channel coil and the saddle-shaped channel coil, respectively. The transceiver switch circuit is used to send the received radio frequency pulse to the solenoid channel coil and the saddle channel coil when a high-level signal is received from the outside; and to receive the magnetic resonance signal collected by the solenoid channel coil and the saddle channel coil when a low-level signal is received from the outside. The transceiver switching circuit includes: a 90-degree bridge, a first quarter-wavelength line, a second quarter-wavelength line, a first diode, a second diode, a third diode, a fourth diode, a first isolation absorption resistor, a second isolation absorption resistor, and a low-noise amplifier; The 90-degree bridge is connected to the solenoid channel coil, the saddle-shaped channel coil, the first quarter-wavelength line, the second quarter-wavelength line, the negative terminal of the second diode, and the positive terminal of the third diode, respectively. The first quarter-wavelength line is connected to the 90-degree bridge, the negative terminal of the second diode, the positive terminal of the first diode, and the first isolation absorption resistor, respectively. The first isolation absorption resistor is connected to the first quarter-wavelength line, the positive terminal of the first diode, and the ground electrode, respectively. The negative terminal of the first diode is connected to the ground electrode. The positive terminal of the second diode is connected to the transmitter, and the negative terminal of the second diode is connected to the first quarter-wavelength line and the 90-degree bridge, respectively. The second quarter-wavelength line is connected to the 90-degree bridge, the positive terminal of the third diode, the positive terminal of the fourth diode, and the low-noise amplifier, respectively; the low-noise amplifier is connected to the positive terminal of the fourth diode, the second quarter-wavelength line, and the receiving end, respectively; the second isolation absorption resistor is connected to the negative terminal of the third diode and the ground electrode, respectively; the fourth diode is connected to the second quarter-wavelength line, the low-noise amplifier, and the ground electrode, respectively. The transceiver switching circuit is specifically configured such that when the high-level signal is received, the first diode, the second diode, the third diode, and the fourth diode are turned on, and one end of the first quarter-wavelength line is short-circuited while the other end is open-circuited, so that the received radio frequency pulse is transmitted to the solenoid channel coil and the saddle channel coil through the second diode and the 90-degree bridge; and when the low-level signal is received, the first diode, the second diode, the third diode, and the fourth diode are not turned on, and the magnetic resonance signal collected by the solenoid channel coil and the saddle channel coil is transmitted to the low-noise amplifier through the 90-degree bridge and the second quarter-wavelength line, and the magnetic resonance signal is amplified by the low-noise amplifier, so that the amplified magnetic resonance signal is sent to the receiving end.

2. The transmitting and receiving system according to claim 1, characterized in that, The solenoid channel coil is a closed coil composed of a first semi-enclosed wire, a second semi-enclosed wire, a first connecting wire, and a second connecting wire; wherein the first semi-enclosed wire and the second semi-enclosed wire are respectively wrapped around the coil shell, and the first semi-enclosed wire and the second semi-enclosed wire are cross-connected by the first connecting wire and the second connecting wire.

3. The transmitting and receiving system according to claim 2, characterized in that, The saddle-shaped channel coil is a closed coil, comprising a first coil group and a second coil group; the first coil group and the second coil group are symmetrically wrapped around the coil shell.

4. The transmitting and receiving system according to claim 3, characterized in that, The first coil group includes a first bow-shaped conductor, a third bow-shaped conductor, a third connecting conductor, and a sixth connecting conductor, wherein one end of the first bow-shaped conductor is connected to one end of the third bow-shaped conductor through the third connecting conductor; The second coil group includes a second bow-shaped conductor, a fourth bow-shaped conductor, a fourth connecting conductor, and a fifth connecting conductor, wherein one end of the second bow-shaped conductor is connected to one end of the fourth bow-shaped conductor through the fourth connecting conductor; The other end of the first bow-shaped conductor is connected to the other end of the fourth bow-shaped conductor via the fifth connecting conductor; The other end of the second bow-shaped conductor is connected to the other end of the third bow-shaped conductor via the sixth connecting conductor; The first and second bow-shaped conductors are located on the same plane; the third and fourth bow-shaped conductors are located on the same plane.

5. The transmitting and receiving system according to claim 1, characterized in that, The transmitter-receiver coil is used to transmit the radio frequency pulse to the human body examination site when it receives the radio frequency pulse sent by the transceiver switch circuit; and when the transceiver switch circuit receives a low-level signal, the transmitter-receiver coil collects the magnetic resonance signal of the human body examination site and sends the magnetic resonance signal to the transceiver switch circuit.

6. The transmitting and receiving system according to claim 4, characterized in that, The first semi-enclosed conductor and the second semi-enclosed conductor are located between the plane containing the first and second bow-shaped conductors and the plane containing the third and fourth bow-shaped conductors; the first semi-enclosed conductor intersects the third connecting conductor at a first intersection point, the fourth connecting conductor at a second intersection point, the fifth connecting conductor at a third intersection point, and the sixth connecting conductor at a fourth intersection point; the second semi-enclosed conductor intersects the third connecting conductor at a fifth intersection point, the fourth connecting conductor at a sixth intersection point, the fifth connecting conductor at a seventh intersection point, and the sixth connecting conductor at an eighth intersection point.

7. The transmitting and receiving system according to claim 6, characterized in that, At the first intersection, the first semi-enclosed wire is between the third connecting wire and the coil housing; at the second intersection, the first semi-enclosed wire is between the fourth connecting wire and the coil housing. At the third intersection, the fifth connecting wire is located between the first semi-enclosed wire and the coil housing; At the fourth intersection, the sixth connecting wire is between the first semi-enclosed wire and the coil housing; at the fifth intersection, the second semi-enclosed wire is between the third connecting wire and the coil housing; at the sixth intersection, the second semi-enclosed wire is between the fourth connecting wire and the coil housing; at the seventh intersection, the fifth connecting wire is between the second semi-enclosed wire and the coil housing. At the eighth intersection, the sixth connecting wire is between the second semi-enclosing wire and the coil housing.

8. The transmitting and receiving system according to claim 1, characterized in that, It also includes a designated receiving coil; the designated receiving coil is disposed inside the coil housing; The designated receiving coil is used to acquire the magnetic resonance signal of the human body examination site when the transmitting receiving coil is used as a transmitting coil and transmits the radio frequency pulse to the human body examination site.

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