Dual-nuclear magnetic resonance coil assembly and dual-nuclear magnetic resonance imaging apparatus

Abstract

The application relates to a dual-nuclear magnetic resonance coil assembly and a dual-nuclear magnetic resonance imaging device. The dual-nuclear magnetic resonance coil assembly comprises a first coil array comprising N first coils, the first coils having a first resonance frequency, N being an integer not less than 4; a second coil array comprising N second coils, the second coils having a second resonance frequency different from the first resonance frequency; and a multi-frequency power divider having N power output terminals configured to selectively output a first radio frequency signal of the first resonance frequency or a second radio frequency signal of the second resonance frequency, the N power output terminals being respectively connected to the N first coils via a respective first resonant circuit and to the N second coils via a respective second resonant circuit, the first resonant circuit resonating at the second resonance frequency and the second resonant circuit resonating at the first resonance frequency.

Description

[0001] This application is a divisional application. The original application has the application number 202510672814.8 and the application date is May 23, 2025. The invention title is Dual-core Magnetic Resonance Coil Assembly and Imaging Device. The full text of the original application is incorporated herein by reference. Technical Field

[0002] This application relates to the field of dual-core magnetic resonance imaging technology, and more particularly to a dual-core magnetic resonance coil assembly and imaging device. Background Technology

[0003] Multinuclear MRI devices, capable of imaging based on the magnetic resonance effect of multiple atomic nuclei, are receiving increasing attention within the MRI industry. Particularly in scientific research, it is significant that MRI devices used in research can be flexibly transformed into various forms and adapted to radio frequency coils of multiple resonant frequencies, in order to conveniently study the performance of multinuclear MRI devices under various conditions. Summary of the Invention

[0004] In view of this, this application proposes a dual-core magnetic resonance coil assembly and an imaging device.

[0005] In a first aspect, a dual-core magnetic resonance coil assembly is provided, comprising: The first coil array includes N first coils arranged circumferentially around the inspection space, each first coil having a first resonant frequency, where N is an integer not less than 4. The second coil array includes N second coils arranged along the circumferential direction and disposed on the outer periphery of the first coil array, wherein the second coils have a second resonant frequency different from the first resonant frequency; A multi-frequency power divider has N power output terminals and level output terminals. The power output terminals are configured to selectively output a first radio frequency signal at a first resonant frequency or a second radio frequency signal at a second resonant frequency. The level output terminals are configured to output a high-level signal in response to the power output terminals outputting the first radio frequency signal, and to output a low-level signal in response to the power output terminals outputting the second radio frequency signal. A switch selection circuit is connected to the level output terminals and configured to connect the N power output terminals to the N first coils respectively in response to the high-level signal, and to connect the N power output terminals to the N second coils respectively in response to the low-level signal.

[0006] In some possible implementations, the switch selection circuit includes: N N-type first transistors, each having a control terminal connected to the level output terminal, a first current terminal connected to the N power output terminals, and a second current terminal connected to the N first coils; N P-type second transistors have control terminals that are all connected to the level output terminals, first current terminals that are respectively connected to the N power output terminals, and second current terminals that are respectively connected to the N second coils.

[0007] In some possible implementations, the second coil array can be detachably mounted to the component and can be replaced by a third or fourth coil array; The third coil array includes N third coils arranged along the circumferential direction and disposed on the outer periphery of the first coil array. The third coils have a third resonant frequency that is different from the first resonant frequency and the second resonant frequency. The fourth coil array includes N fourth coils arranged along the circumferential direction and disposed on the outer periphery of the first coil array. The fourth coils have a fourth resonant frequency that is different from the first resonant frequency, the second resonant frequency and the fourth operating frequency. The power output terminal is further configured to selectively output a third radio frequency signal at the third resonant frequency or a fourth radio frequency signal at the fourth resonant frequency, and the level output terminal is further configured to output a low-level signal in response to the power output terminal outputting either the third radio frequency signal or the fourth radio frequency signal.

[0008] In some possible implementations, the second coil includes an adjustable capacitor, and by adjusting the capacitance value of the adjustable capacitor, the resonant frequency of the second coil can be adjusted to either a third resonant frequency or a fourth resonant frequency. The power output terminal is further configured to selectively output a first radio frequency signal at the third resonant frequency or a fourth radio frequency signal at the fourth resonant frequency, and the level output terminal is further configured to output a low-level signal in response to the power output terminal outputting either the third radio frequency signal or the fourth radio frequency signal.

[0009] In some possible implementations, the first coil includes an adjustable capacitor, and by adjusting the capacitance value of the adjustable capacitor, the resonant frequency of the first coil can be adjusted to either a third resonant frequency or a fourth resonant frequency. The power output terminal is further configured to selectively output a third radio frequency signal at the third resonant frequency or a fourth radio frequency signal at the fourth resonant frequency, and the level output terminal is further configured to output a high-level signal in response to the power output terminal outputting either the third radio frequency signal or the fourth radio frequency signal.

[0010] In some possible implementations, the first resonance frequency, the second resonance frequency, the third resonance frequency, and the fourth resonance frequency correspond to the Larmor frequencies of the sodium nucleus, the hydrogen nucleus, the fluorine nucleus, and the phosphorus nucleus, respectively.

[0011] Secondly, a dual-core magnetic resonance coil assembly is proposed, comprising: The first coil array includes N first coils arranged circumferentially around the inspection space, each first coil having a first resonant frequency, where N is an integer not less than 4. The second coil array includes N second coils arranged along the circumferential direction and disposed on the outer periphery of the first coil array, wherein the second coils have a second resonant frequency different from the first resonant frequency; A multi-frequency power divider has N power output terminals, which are configured to selectively output a first radio frequency signal at a first resonant frequency or a second radio frequency signal at a second resonant frequency. The N power output terminals are respectively connected to the N first coils via their respective first resonant circuits and respectively connected to the N second coils via their respective second resonant circuits, wherein the first resonant circuits resonate at the second resonant frequency and the second resonant circuits resonate at the first resonant frequency.

[0012] Thirdly, a dual-nuclear magnetic resonance imaging device is provided, comprising: Components as described in the first or second aspect; An inner housing that internally defines the inspection space; The outer shell is detachably mounted to the inner shell and defines an installation space between the outer shell and the inner shell; The first coil array, the second coil array, the multi-frequency power divider, and the switch selection circuit are all disposed within the mounting space and are all supported by the inner housing, but not by the outer housing.

[0013] In some possible implementations, including: An RF transmitter, connected to the power input terminal of the multi-frequency power divider, is configured to provide an RF signal to the power input terminal.

[0014] According to the dual-core magnetic resonance coil assembly provided in this application, the dual-core magnetic resonance imaging device can adapt to changes in coil frequency without replacing electronic components such as the power divider, thereby facilitating the study of magnetic resonance imaging effects of different atomic nuclei. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings of the embodiments will be briefly described below. Obviously, the drawings described below only relate to some embodiments of this application, and are not intended to limit this application.

[0016] Figure 1 This is a schematic diagram of the appearance of the dual-nuclear magnetic resonance imaging device provided in the embodiments of this application.

[0017] Figure 2 yes Figure 1 The diagram shown is a schematic of the structure after the outer shell has been removed.

[0018] Figure 3 yes Figure 1 The diagram shown is a schematic of the structure after the outer shell has been removed.

[0019] Figure 4 Observing from another perspective Figure 3 A schematic diagram.

[0020] Figure 5 yes Figure 4 A magnified view of a portion of the image.

[0021] Figure 6 Observing from another perspective Figure 1 A schematic diagram.

[0022] Figure 7 This is a schematic diagram showing the distribution of the first and second coil arrays.

[0023] Figure 8 This is a flowchart of the assembly method of the dual-nuclear magnetic resonance imaging device provided in the embodiments of this application.

[0024] Figure 9 This is a circuit connection diagram of the dual-core magnetic resonance coil assembly provided in the embodiments of this application.

[0025] Figure 10 This is a circuit connection diagram of a dual-core magnetic resonance coil assembly provided in another embodiment of this application.

[0026] Explanation of reference numerals in the attached figures: Assembly methods for 100-dual-nuclear magnetic resonance imaging device and 200-dual-nuclear magnetic resonance imaging device; 50-Dual-core magnetic resonance coil assembly; F1 - Axial direction, F2 - Radial direction, F3 - Circumferential direction; SP1 - Inspection space, SP2 - Installation space; dd - radial spacing; 1-First coil; 2 - Second coil, 2U - High-position coil, 2D - Low-position coil; 3-Shell; 4-Inner shell, 4a-Mounting bracket, 4a1-Plate base; 5-Outer shell; 6-Supporting components; 7-Lifting components; 8-Horizontal bar, 8a-Slot, 8b-Second side; 9-Support ring, 9a-First segment, 9b-Support surface, 9c-Second surface; 10-Screw; 11-Adjusting nut; 12-Guide post; 13-Support; 14-Base portion; 15 - The substrate of the test subject; 16 - First coil array, 17 - Second coil array; 18-Cylinder body; 19 - Upper back cover; 20-Lower Rear Cover 21-Power divider; 22-Outgoing junction box; 23-Guard plate; 24-Switch selection circuit; M1 - First transistor, M2 - Second transistor; P1 - Power input terminal, P2 - Power output terminal, P3 - Level output terminal. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages 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, not all, of the embodiments of this application. Based on the described embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. It is understood that, without conflict, some technical means of the various embodiments described herein can be substituted for or combined with each other.

[0028] In the description of this application, the terms "first," "second," etc., are used only to distinguish the described objects and have no sequential or technical meaning. Therefore, objects specified with "first," "second," etc., may explicitly or implicitly include one or more of those objects, and, for example, the term "first element" itself does not imply the existence of a "second element," nor does the term "second element" itself imply the existence of a "first element." Furthermore, words such as "a" or "one" do not indicate a quantity limitation, but rather indicate the presence of at least one, while "multiple" indicates not less than two.

[0029] In the description of this application, the terms "comprising" or "having" indicate the presence of the said features, numbers, operations, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, numbers, operations, elements, and / or combinations thereof.

[0030] In the description of this application, if there are terms such as “configured as” or “constructed as”, they are generally interchangeable with “having the ability to”, “designed to”, “used for” or “capable”, depending on the context.

[0031] In the description of this application, references to "one embodiment" or "some embodiments" mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized.

[0032] Figures 1 to 7 A specific embodiment of the dual-nuclear magnetic resonance imaging apparatus 100 (hereinafter, sometimes simply referred to as apparatus 100) of this application is shown. The apparatus 100 includes a support 13, a housing 3 supported by the support 13, and a first coil array 16 and a second coil array 17 mounted within the housing 3.

[0033] The housing 3 includes an inner housing 4 and an outer housing 5 detachably fixed to the inner housing 4. A mounting space SP2 is formed between the inner housing 4 and the outer housing 5 to accommodate electronic components such as the first coil array 16, the second coil array 17, and electronic components such as the power divider 21 (described later) and a preamplifier (not shown). The inner housing 4 and the outer housing 5 can be molded structures made of plastic, with the inner housing 4 constructed as a single integral part, while the outer housing 5 is composed of multiple separate components. Based on this design, the outer housing 5 can be easily fixed to the inner housing 4 after the first coil array 16 and the second coil array 17 have been mounted onto the inner housing 4.

[0034] The inner housing 4 defines an inspection space SP1 on its inner circumferential side, which accommodates the test object and is surrounded by the aforementioned mounting space SP2. The inspection space SP1 defines an axial direction F1, a radial direction F2 and a circumferential direction F3. The inspection space SP1 has an opening that opens to the front end of the axial direction F1 and is closed to the rear end of the inspection space SP1.

[0035] The support 13 has a base portion 14 for supporting the housing 3 and a subject-bearing portion 15 for supporting the subject. Figure 1 In this design, the subject support portion 15 is formed as an arc-shaped plate adapted to the contour and size of the human head, thus making it suitable for magnetic resonance imaging examination of the human head. Furthermore, the subject support portion 15 is detachably fixed to the base portion 14 via screws (not shown), allowing it to be replaced with other configurations of the subject support portion 15 suitable for supporting other subjects (e.g., small animals).

[0036] The first coil array 16 includes a plurality of rectangular first coils 1 arranged along the circumferential direction F3, with any two adjacent first coils 1 partially overlapping each other to decouple. The first coils 1 are attached to and fixed to the outer surface of the inner housing 4, i.e., the surface opposite to the inspection space SP1, so that the first coils 1 are sufficiently close to the inspection space SP1 and the subject. In addition, the two short sides of the rectangular first coil 1 extend along the circumferential direction F3, and the two long sides extend along the axial direction F1 perpendicular to the circumferential direction F3.

[0037] The second coil array 17 includes a plurality of circular second coils 2 arranged along the circumferential direction F3, and the second coil array 17 is arranged on the outer periphery of the first coil array 16 at a predetermined radial interval dd. Therefore, the second coils 2 are further away from the examination space SP1 and the subject than the first coils 1. In addition, the second coils 2 and the first coils 1 have different resonant frequencies, which can correspond to the Larmor frequencies of two different atomic nuclei, respectively, so that magnetic resonance images of the subject can be acquired based on the magnetic resonance effects of the two atomic nuclei.

[0038] In this embodiment, both the first coil 1 and the second coil 2 are integrated transceiver coils. On one hand, the first coil array 16 can transmit a radio frequency signal corresponding to the Larmor frequency of the first type of atomic nucleus to generate a B1 field at the examination space SP1, thereby exciting the first type of atomic nucleus within the test subject to generate a magnetic resonance signal. The first coil array 16 then receives the magnetic resonance signal of the first type of atomic nucleus, and a magnetic resonance image of the test subject is obtained based on the magnetic resonance effect of the first type of atomic nucleus. On the other hand, the second coil array 17 can also transmit a radio frequency signal corresponding to the Larmor frequency of the second type of atomic nucleus to generate a B1 field with another characteristic at the examination space SP1, thereby exciting the second type of atomic nucleus within the test subject to generate a magnetic resonance signal. The second coil array 17 then receives the magnetic resonance signal of the second type of atomic nucleus, and a magnetic resonance image of the test subject is obtained based on the magnetic resonance effect of the second type of atomic nucleus. Furthermore, in some embodiments, the magnetic resonance image based on the first type of atomic nucleus and the magnetic resonance image based on the second type of atomic nucleus can be fused to obtain a higher quality fused magnetic resonance image.

[0039] The first type of atomic nucleus and the second type of atomic nucleus can be any two of the following: hydrogen nucleus, phosphorus nucleus, carbon nucleus, sodium nucleus, and fluorine nucleus.

[0040] Furthermore, in the axial direction F1, the size of the rectangular first coil 1 unit can be the same as the size of the circular second coil 2 unit. Also, the second coil array 17 and the first coil array 16 can be separated by 20mm in the radial direction F2. The diameter of the circular second coil 2 unit can be 150mm, and the length and width of the rectangular first coil 1 can be 150mm and 100mm respectively.

[0041] In this embodiment, the plurality of second coils 2 constituting the second coil array 17 are positioned within the mounting space SP2 via a plurality of support components 6. Furthermore, by operating the support components 6, the radial position of the second coils 2 can be adjusted, i.e., the size of the aforementioned radial spacing dd can be adjusted. When the first coil array 16 and the second coil array 17 are separated from each other by a radial spacing dd, the coupling interference between the two coil arrays can be significantly reduced, contributing to high-quality extraction of magnetic resonance signals from the respective coil arrays. Generally, the larger the radial spacing dd, the lower the coupling interference between the two coil arrays. However, a large radial spacing dd increases the distance between the outer peripheral second coil array 17 and the examination space SP1 and the subject, resulting in a decrease in the transmission efficiency and receiving sensitivity of the second coils 2. Therefore, it is necessary to find the optimal radial spacing dd to balance low coupling between the two coil arrays with the transmission efficiency and receiving sensitivity of each coil array, so as to easily obtain magnetic resonance images of the highest possible quality.

[0042] Furthermore, factors affecting the quality of magnetic resonance images include not only the radial spacing dd between the first coil array 16 and the second coil 2, but also the type of atomic nuclei targeted by the coils (which determines their resonance / operating frequency) and the biological characteristics of the subject. For example, even when the first coil array 16 is present on the inner periphery, the second coil array 17 exhibits excellent magnetic resonance imaging performance for sodium nuclei at the same location (i.e., the same location of the second coil array 17). However, when this second coil array 17 is tuned and used for phosphorus-based magnetic resonance imaging, it may exhibit relatively poor magnetic resonance imaging performance. But by changing the radial position of the tuned second coil array 17 (adjusting it further away or closer), it can exhibit excellent magnetic resonance imaging performance for phosphorus nuclei again. Moreover, the proportion of atomic nuclei varies for different types of subjects; therefore, it is necessary to design the resonance frequencies of the first coil array 16 and the second coil array 17 accordingly for different subjects.

[0043] Advantageously, the radial position of the second coil array 17 of the dual-nuclear magnetic resonance imaging device provided in this application embodiment can be easily adjusted. Therefore, for the various applications mentioned above, the operator can easily find the optimal radial spacing dd based on experimental testing. Thus, the device is particularly suitable for the scientific research field.

[0044] Specifically, multiple support components 6 are arranged along the circumferential direction F3 within the mounting space SP2 and supported by the inner housing 4. Therefore, even when the outer housing 5 is removed, the second coil 2 can still maintain its relative position to the inspection space SP1, and thus, the outer housing 5 can be installed after the support components 6 and the second coil 2 are installed into the inner housing 4. Since the first coil 1, support components 6, and second coil 2 are all disposed on the outer surface side of the inner housing 4, sufficient operating space is provided for the assembler of the device 100 to install the first coil 1, support components 6, and second coil 2 before the outer housing 5 is installed into the inner housing 4. The support component 6 includes a lifting member 7 detachable from the support component 6 and supporting the second coil 2. The lifting member 7 is configured to selectively approach or move away from the inner housing 4, thereby adjusting the size of the aforementioned radial spacing dd. Furthermore, since the lifting member 7 is detachable from the support component 6, it can... Figures 2 to 5 The lifting member 7 in the middle is replaced with a lifting member 7 of other configurations to carry coils of other configurations, such as a third coil or a fourth coil that is different from the second coil 2.

[0045] The lifting component 7 includes a crossbar 8 and a support ring 9. The crossbar 8 extends in a straight line along the axial direction F1. In some embodiments, the crossbar 8 is capable of carrying a monopole coil. The support ring 9 is fixed to both ends of the crossbar 8 and supports the second coil 2. The support ring 9 has a three-dimensional shape and defines a support surface 9b extending radially outward along the circumferential direction F3 and the axial direction F1. The second coil 2 extends on the support surface 9b, thus the second coil 2 becomes a non-planar three-dimensional shape. This helps to reduce the thickness of the installation space SP2 and the structural compactness of the lifting device 100, avoiding an enlarged outer dimension of the housing 3.

[0046] The support assembly 6 includes a screw 10 and two adjusting nuts 11. The screw 10 extends radially F2 from the inner housing 4 and passes through the crossbar 8. The two adjusting nuts 11 are screwed onto the screw 10 on opposite sides of the crossbar 8 in the radial direction F2. By rotating and adjusting the position of these two adjusting nuts 11 relative to the screw 10, the position of the crossbar 8 (and the support ring 9) relative to the screw 10 can be changed, thereby adjusting the aforementioned radial spacing dd. Additionally, one of the two adjusting nuts 11 (the one on the inner radial side) is obscured in the figures due to size and viewing angle, and is therefore not shown.

[0047] The support assembly 6 also includes two guide posts 12. The two guide posts 12 extend radially from the inner housing 4 in the direction F2 and are respectively disposed on opposite sides of the screw 10 in the axial direction F1. The guide posts 12 pass through the crossbar 8, thereby guiding the position adjustment of the lifting member 7 and the second coil 2 in the radial direction F2 and restricting the rotation of the lifting member 7 and the second coil 2 about the screw 10. In this embodiment, the guide posts 12 are integrally formed on the outer surface of the inner housing 4 as plastic parts, the screw 10 is a metal part detachably fixed to the outer surface of the inner housing 4 by screws (not shown), and the cross-section of the guide posts 12 is formed as a flat shape extending in the axial direction F1.

[0048] The end of the crossbar 8 has a recessed groove 8a in the axial direction F1, and the groove 8a extends through the end of the crossbar 8 in the circumferential direction F3. A portion of the first section 9a of the support ring 9 is detachably inserted into the groove 8a, and the remaining portion of the first section 9a is located outside the groove 8a in the axial direction F1, defining a stepped surface including a first surface 8b and a second surface 9c that intersect each other. A portion of the second coil 2 is abutted against the first surface 8b and the second surface 9c. With this design, the mounting position of the second coil 2 on the support ring 9 can be easily positioned, and the individual second coils 2 can be easily constructed to have substantially uniform dimensions, so as to have excellent signal uniformity when the second coil array 17 is operating in the transmission mode.

[0049] In some embodiments, the axial distance between the two guide posts 12 can be increased so that the two guide posts 12 are positioned close to the first coil 1 on its inner circumference. With this design, the mounting position of the first coil 1 can be positioned using the guide posts 12, and the individual first coils 1 can be easily constructed to have substantially uniform dimensions, so as to have excellent signal uniformity when the first coil array 16 is operating in transmit mode.

[0050] In this embodiment, the two guide posts 12 have the same height, and the tops of the guide posts 12 contact or are adjacent to the inner surface of the outer casing 5. This design provides good radial support for the outer casing 5 and the inner casing 4, preventing the inner casing 4 from shifting relative to the outer casing 5 and causing positional changes in the internal coils. This is especially important when the device 100 is used with the axial direction F1 as its horizontal orientation, where the inner casing 4 tends to sag downwards (corresponding to a radial direction F2) due to its own weight and the weight of the coil array and related electronic components. In other embodiments, the test subject support 15 of the support 13 is omitted, and the test subject is directly supported by the inner casing 4. In this case, the tendency of the inner casing 4 to sag relative to the outer casing 5 is more pronounced.

[0051] The tip of the screw 10 is lower than the tip of the guide post 12, thus ensuring that when one of the adjusting nuts 11 is at the tip of the screw 10, the crossbar 8 is below the tip of the guide post 12. This prevents the crossbar 8 from exceeding the tip of the guide post 12 and interfering with the installation of the housing 5, even if the researchers adjust the second coil 2 to its maximum permissible height using the adjusting nut 11. More importantly, it avoids mechanical damage to the second coil 2 caused by the housing 5 being set too high. Furthermore, setting the tip of the screw 10 lower than the tip of the guide post 12 prevents the tip of the screw 10 from interfering with the installation of the housing 5.

[0052] In this embodiment, portions of any two adjacent lifting members 7 overlap each other; more specifically, portions of any two adjacent support rings 9 overlap each other, thereby causing portions of any two adjacent second coils 2 to overlap each other for decoupling.

[0053] The rear end of the inner housing 4 along the axial direction F1 is integrally formed with a mounting bracket 4a for mounting the power divider 21 and the preamplifier. The rear end of the mounting bracket 4a has a plate base 4a1. A cable outlet box 22, shown in dashed lines, is connected to the side of the plate base 4a1 opposite to the inner housing 4 along the axial direction F1 and is formed to be larger than the size of the connecting member. In addition, the cable (not shown) is connected to the power divider 21 and the preamplifier via the cable outlet box 22. The outer housing 5 includes a cylindrical body 18, an upper rear cover 19, and a lower rear cover 20. The cylindrical body 18 is a one-piece molded part with a first end and a second end that are open to each other along the axial direction F1. The first end is fixed to the outer lip of the inner housing 4. The upper rear cover 19 is also a one-piece molded part, which is detachably fixed to the cylindrical body 18 and closes the upper half of the second end. The lower rear cover 20 is also a one-piece molded part, which is detachably fixed to the cylindrical body 18 and closes the lower half of the second end. The upper rear cover 19 and the lower rear cover 20 define an opening that surrounds the plate base 4a1. The lower rear cover 20 supports the plate base 4a1 through the lower half of the opening, and the cable outlet box 22 is located outside the opening. This design allows the outer shell 5 to be easily assembled into the inner shell 4, ensuring the support of the outer shell 5 for the inner shell 4 and the coaxiality between the inner shell 4 and the outer shell 5.

[0054] Additionally, please see Figure 3 The housing 3 also includes an arc-shaped support plate fixed to the outer surface of the bottom of the outer shell 5. The arc-shaped support plate helps to strengthen the structural strength of the housing 3, especially the outer shell 5, at the bottom, because the weight of the housing 3 is applied to the support 13 through its bottom.

[0055] The plurality of second coils 2 constituting the second coil array 17 consist of low coils 2D and high coils 2U arranged alternately along the circumferential direction F3, with each high coil 2U located on the outer periphery of two adjacent low coils 2D.

[0056] Now, please see Figure 8 And combined Figures 2 to 5 As shown, this application embodiment also provides an assembly method 200 for the device 100, the method 200 including: S801, before the outer shell 5 and the multiple lifting components 7 are installed into the inner shell 4, multiple first coils 1 are installed into the inner shell 4, and multiple second coils 2 are respectively installed into the multiple lifting components 7.

[0057] S802, each lifting component 7 (referred to as the first lifting component 7 for ease of description) with a low-position coil 2D installed is respectively fitted onto the corresponding screw 10. The height of one of the first lifting components 7 (referred to as the reference lifting component 7 for ease of description) is adjusted so that the radial distance dd between the low-position coil 2D on it and the corresponding first coil 1 becomes a set value. Then, the reference lifting component 7 is fixed by adjusting nut 11.

[0058] S803, each lifting component 7 (referred to as the second lifting component 7 for ease of description) with the high-position coil 2U installed is respectively fitted onto the corresponding screw 10, the height of the second lifting component 7 (referred to as the second reference lifting component 7 for ease of description) adjacent to the reference lifting component 7 is adjusted so that the second reference lifting component 7 contacts the reference lifting component 7 radially inward, and then the second reference lifting component 7 is fixed by adjusting nut 11.

[0059] S804, adjust the height of another first lifting member 7 adjacent to the second reference lifting member 7 so that the other first lifting member 7 contacts the reference lifting member 7 radially outward, and then fix the other first lifting member 7 with the adjusting nut 11; and so on, until all the lifting members 7 are fixed by the corresponding adjusting nuts 11. S805, install the outer casing 5 onto the inner casing 4.

[0060] Understandably, method 200 allows each second coil 2 to be easily positioned at the desired height, simplifying the assembly of device 100.

[0061] Please go to [link / direction] now. Figure 9 , Figure 9 The connection circuit between the two coil arrays and the power divider 21 in the device 100 is shown. The power divider 21 has at least one power input terminal P1, eight power output terminals P2, and one level output terminal P3. The eight power output terminals P2 can simultaneously output a first radio frequency signal at a first resonant frequency or simultaneously output a second radio frequency signal at a second resonant frequency. The level output terminal P3 is configured to output a high-level signal in response to the first radio frequency signal output by the power output terminal P2, and to output a low-level signal in response to the second radio frequency signal output by the power output terminal P2. The level output terminal P3 outputs a high-level signal or a low-level signal according to the frequency of the radio frequency signal, which can be implemented using a latch circuit or a frequency selection circuit, and will not be elaborated here.

[0062] Because this power divider 21 can output radio frequency power signals of multiple frequencies (including at least the first and second resonant frequencies) as needed, it can be called a multi-frequency power divider 21. Furthermore, in Figure 9The combination of the first coil array 16, the second coil array 17, the power divider 21, and the switch selection circuit 24 shown in the figure can be referred to as the dual-core magnetic resonance coil assembly 50.

[0063] Furthermore, the switch selection circuit 24 is connected to the level output terminal P3 of the power divider 21 and is configured to connect the eight power output terminals P2 to the eight first coils 1 respectively in response to a high-level signal, and to connect the eight power output terminals P2 to the eight second coils 2 respectively in response to a low-level signal. That is, the operating state of the switch selection circuit 24 is controlled by the level output terminal P3 of the power divider 21.

[0064] More specifically, the first resonance frequency corresponds to the Larmor frequency of the sodium nucleus, and the second resonance frequency corresponds to the Larmor frequency of the hydrogen nucleus.

[0065] The device 100 also includes an RF transmitter (not shown), which is disposed on the outside of the housing 3 and electrically connected to the power input terminal P1 of the power divider 21, for example, via an RF power amplifier. When the device 100 needs to operate in sodium core emission mode, the RF transmitter can provide a first RF signal at a first resonant frequency to the power input terminal P1 of the power divider 21. Under the action of the first RF signal, the level output terminal P3 of the power divider 21 outputs a high-level signal, thereby causing the switch selection circuit 24 to couple the eight power output terminals P2 of the power divider 21 to the eight first coils 1 of the first coil array 16, respectively. Furthermore, the power divider 21 divides the received first RF signal into eight equal-power paths, which are then transmitted to the eight first coils 1 of the first coil array 16 via the eight power output terminals P2, respectively.

[0066] When the device 100 needs to operate in the hydrogen nucleus emission mode, the radio frequency transmitter provides a second radio frequency signal with the second resonant frequency to the power input terminal P1 of the power divider 21. Under the action of the second radio frequency signal, the level output terminal P3 of the power divider 21 outputs a high-level signal, thereby causing the switch selection circuit 24 to couple the eight power output terminals P2 of the power divider 21 to the eight second coils 2 of the second coil array 17 respectively. At the same time, the power divider 21 divides the second radio frequency signal it receives into eight paths with equal power, and transmits them to the eight second coils 2 of the second coil array 17 respectively via the eight power output terminals P2.

[0067] like Figure 9As shown, the switch selection circuit 24 includes eight first transistors M1 and eight second transistors M2. The eight first transistors M1 each have a control terminal (gate terminal) connected to the level output terminal P3, first current terminals connected to the eight power output terminals P2, and second current terminals connected to the eight first coils 1, wherein the first and second current terminals can be the source and drain of the transistor, respectively. The eight second transistors M2 each have a control terminal (gate terminal) connected to the level output terminal P3, first current terminals connected to the eight power output terminals P2, and second current terminals connected to the eight second coils 2, wherein the first and second current terminals can be the drain and source of the transistor, respectively. Thus, when the power divider 21's output terminal P3 applies a high-level signal to the control terminals of the eight first transistors M1 and eight second transistors M2, each first transistor M1 is turned on and each second transistor M2 is turned off. The switch selection circuit 24 couples the power divider 21 to the first coil array 16 and decouples the power divider 21 from the second coil array 17. When the power divider 21's output terminal P3 applies a low-level signal to the control terminals of the eight first transistors M1 and eight second transistors M2, each first transistor M1 is turned off and each second transistor M2 is turned on. The switch selection circuit 24 couples the power divider 21 to the second coil array 17 and decouples the power divider 21 from the first coil array 16.

[0068] As described above, in the embodiments of this application, the lifting member 7 of the device can be replaced with a lifting member 7 of other configurations to carry a third coil or a fourth coil different from the second coil 2, thereby forming a third coil array or a fourth coil array. Since the third coil has a third resonant frequency different from the second resonant frequency, and the fourth coil has a fourth resonant frequency different from the second resonant frequency, in order for the device 100 to adapt to such a third coil array and a fourth coil array without replacing electronic components such as the power divider 21, the embodiments of this application further configure the power divider 21 such that the eight power output terminals P2 can simultaneously output a third radio frequency signal with the third resonant frequency or simultaneously output a fourth radio frequency signal with the fourth resonant frequency. Furthermore, the level output terminal P3 of the power divider 21 is configured to output a low-level signal in response to the power output terminal P2 outputting a third radio frequency signal with the third resonant frequency, and to output a low-level signal in response to the power output terminal P2 outputting a fourth radio frequency signal with the fourth resonant frequency.

[0069] In order to easily implement the level output terminal P3 to output a high-level signal in response to the radio frequency signal at the first resonant frequency, and to output a low-level signal in response to the radio frequency signal at the second, third or fourth resonant frequency, the second, third and fourth resonant frequencies can all be selected as frequencies higher than the first resonant frequency.

[0070] In some more specific embodiments, the frequency of the third radio frequency signal, i.e., the third resonant frequency, corresponds to the Larmor frequency of the fluorine nucleus, and the frequency of the fourth radio frequency signal, i.e., the fourth resonant frequency, corresponds to the Larmor frequency of the phosphorus nucleus. Therefore, when the second coil array 17 is replaced by the third coil array, the device 100 can be used for dual-nuclear magnetic resonance imaging of the sodium and fluorine nuclei; and when the second coil array 17 is replaced by the fourth coil array, the device 100 can be used for dual-nuclear magnetic resonance imaging of the sodium and phosphorus nuclei.

[0071] In some embodiments, the resonant frequency of the second coil 2 can be adjusted to a value different from the second resonant frequency as needed. Specifically, the second coil 2 includes at least one adjustable capacitor, and by adjusting the capacitance value of the adjustable capacitor, the resonant frequency of the second coil 2 can be changed, such as to the aforementioned third or fourth resonant frequency. With such a design, magnetic resonance imaging based on other atomic nuclei such as fluorine nuclei, phosphorus nuclei, etc., can be performed without replacing the second coil 2.

[0072] In other embodiments, the first coil 1 includes at least one adjustable capacitor. By adjusting the capacitance value of the adjustable capacitor, the resonant frequency of the first coil 1 can be changed, so that the first coil 1 can be used for magnetic resonance imaging of atomic nuclei other than sodium nuclei, such as changing the resonant frequency of the first coil 1 to the aforementioned third or fourth resonant frequency. Furthermore, to achieve radio frequency isolation from the second coil 2, in such embodiments, the level output terminal P3 of the power divider 21 can be configured to output a low-level signal in response to the output of either a third radio frequency signal at the third resonant frequency or a fourth radio frequency signal at the fourth resonant frequency by the power output terminal P2.

[0073] In another possible embodiment, such as Figure 10As shown, the eight power output terminals P2 of the power divider 21 are connected to the eight first coils 1 respectively via the first parallel resonant circuit composed of capacitor C1 and inductor L1, and are also connected to the eight second coils 2 respectively via the second parallel resonant circuit composed of capacitor C2 and inductor L2. The first parallel resonant circuit resonates at the second resonant frequency, and the second parallel resonant circuit resonates at the first resonant frequency. Therefore, when the power output terminal P2 of the power divider 21 outputs a first radio frequency signal at the first resonant frequency, the first radio frequency signal is blocked by the second parallel resonant circuit resonating at the first resonant frequency, and thus cannot be transmitted to the second coil 2. However, it can be transmitted to the first coil 1 via the first parallel resonant circuit that does not resonate at the first resonant frequency. That is, the power output terminal P2 is coupled to the first coil 1, but decoupled from the second coil 2. When the power output terminal P2 of the power divider 21 outputs a second radio frequency signal at the second resonant frequency, the second radio frequency signal is blocked by the first parallel resonant circuit resonating at the second resonant frequency, and thus cannot be transmitted to the first coil 1. However, it can be transmitted to the second coil 2 via the second parallel resonant circuit that does not resonate at the second resonant frequency. That is, the power output terminal P2 is coupled to the second coil 2, but decoupled from the first coil 1.

[0074] Although the number of coils in the two coil arrays on the inner and outer circumference sides is set to 8 in the discussion above, it is understood that the number of coils in these two coil arrays can also be designed to other values, such as 4 or 16. Accordingly, the power divider 21 has at least a corresponding number of power output terminals P2, which will not be elaborated here.

Claims

1. A dual-core magnetic resonance coil assembly, characterized in that, include: The first coil array includes N first coils, each first coil having a first resonant frequency, where N is an integer not less than 4; The second coil array includes N second coils, each second coil having a second resonant frequency different from the first resonant frequency; A multi-frequency power divider has N power output terminals, which are configured to selectively output a first radio frequency signal at a first resonant frequency or a second radio frequency signal at a second resonant frequency. The N power output terminals are respectively connected to the N first coils via their respective first resonant circuits and respectively connected to the N second coils via their respective second resonant circuits, wherein the first resonant circuits resonate at the second resonant frequency and the second resonant circuits resonate at the first resonant frequency.

2. The component according to claim 1, characterized in that, The N first coils are arranged circumferentially around the inspection space, and the N second coils are arranged circumferentially on the outer periphery of the first coil array.

3. The component according to claim 2, characterized in that, Also includes: A plurality of support components arranged along the circumferential direction, each support component including a lifting member detachable from the support component and supporting the second coil, each of the lifting members being configured to selectively move closer to or further away from the inner housing, thereby adjusting the size of the radial spacing between the first coil array and the second coil.

4. The component according to claim 1, characterized in that, The second coil includes an adjustable capacitor, and by adjusting the capacitance value of the adjustable capacitor, the resonant frequency of the second coil can be adjusted to either a third resonant frequency or a fourth resonant frequency, wherein the first resonant frequency, the second resonant frequency, the third resonant frequency and the fourth resonant frequency correspond to the Larmor frequencies of four different atomic nuclei, respectively. The power output terminal is further configured to selectively output a third radio frequency signal at the third resonant frequency or a fourth radio frequency signal at the fourth resonant frequency, and the level output terminal is further configured to output a low-level signal in response to the power output terminal outputting either the third radio frequency signal or the fourth radio frequency signal.

5. The component according to claim 1, characterized in that, The first coil includes an adjustable capacitor, and by adjusting the capacitance value of the adjustable capacitor, the resonant frequency of the first coil can be adjusted to either the third resonant frequency or the fourth resonant frequency. The power output terminal is further configured to selectively output a third radio frequency signal at the third resonant frequency and a fourth radio frequency signal at the fourth resonant frequency, and the level output terminal is further configured to output a high-level signal in response to the power output terminal outputting either the third radio frequency signal or the fourth radio frequency signal.

6. A dual-nuclear magnetic resonance imaging device, characterized in that, include: The component as described in any one of claims 1 to 5; The housing includes an inner housing, an outer housing, and an installation space defined between the inner housing and the outer housing, the interior of the inner housing defining an inspection space; The first coil array, the second coil array, the multi-frequency power divider, and the switch selection circuit are all configured within the installation space.

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