CN116482592A - Receiving coil device for magnetic resonance imaging and magnetic resonance imaging system - Google Patents
Receiving coil device for magnetic resonance imaging and magnetic resonance imaging system Download PDFInfo
- Publication number
- CN116482592A CN116482592A CN202310116301.XA CN202310116301A CN116482592A CN 116482592 A CN116482592 A CN 116482592A CN 202310116301 A CN202310116301 A CN 202310116301A CN 116482592 A CN116482592 A CN 116482592A
- Authority
- CN
- China
- Prior art keywords
- conductor
- intermediate conductor
- magnetic resonance
- cylindrical surface
- coil arrangement
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000002595 magnetic resonance imaging Methods 0.000 title claims abstract description 51
- 239000004020 conductor Substances 0.000 claims abstract description 281
- 239000012777 electrically insulating material Substances 0.000 claims description 10
- 230000000295 complement effect Effects 0.000 claims description 3
- 239000003990 capacitor Substances 0.000 abstract description 8
- 238000003384 imaging method Methods 0.000 description 10
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 8
- 229910052739 hydrogen Inorganic materials 0.000 description 8
- 239000001257 hydrogen Substances 0.000 description 8
- 230000003068 static effect Effects 0.000 description 6
- 230000008878 coupling Effects 0.000 description 5
- 238000010168 coupling process Methods 0.000 description 5
- 238000005859 coupling reaction Methods 0.000 description 5
- 230000005415 magnetization Effects 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 230000005281 excited state Effects 0.000 description 2
- 210000003127 knee Anatomy 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 241000219195 Arabidopsis thaliana Species 0.000 description 1
- 210000003484 anatomy Anatomy 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000002059 diagnostic imaging Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005674 electromagnetic induction Effects 0.000 description 1
- 230000014509 gene expression Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
- G01R33/32—Excitation or detection systems, e.g. using radio frequency signals
- G01R33/36—Electrical details, e.g. matching or coupling of the coil to the receiver
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/05—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves
- A61B5/055—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
- G01R33/38—Systems for generation, homogenisation or stabilisation of the main or gradient magnetic field
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
- Y02A90/30—Assessment of water resources
Abstract
The present application relates to a receive coil arrangement for magnetic resonance imaging and a magnetic resonance imaging system comprising: a first end conductor and a second end conductor that collectively define at least a portion of a cylindrical surface; a plurality of first capacitances dividing the first end conductor into a plurality of first ring segments and a plurality of second capacitances dividing the second end conductor into a plurality of second ring segments; a plurality of decoupling circuits alternately connected in parallel to a corresponding one of the capacitors in a circumferential direction of the cylindrical surface, respectively; and a plurality of first intermediate conductors arranged in sequence in a circumferential direction of the cylindrical surface, at least a portion of each first intermediate conductor having a first spiral shape with respect to the cylindrical surface, a first end of each first intermediate conductor being connected to a respective one of the first ring segments and a second end of each first intermediate conductor being connected to a respective one of the second ring segments corresponding to the respective one of the first ring segments. The device and system of the present application are structurally improved to improve brightness uniformity of the image, achieve decoupling, and improve uniformity of the magnetic field.
Description
Technical Field
The present application relates to the field of magnetic resonance imaging, and more particularly to a receive coil arrangement for magnetic resonance imaging and a magnetic resonance imaging system.
Background
Magnetic Resonance Imaging (MRI) is a medical imaging modality that can produce images of the interior of a patient without X-ray radiation or other types of ionizing radiationLike an image. MRI systems utilize superconducting magnets to generate a strong and uniform static magnetic field B within an imaging region (e.g., within a tunnel shaped to receive a patient) 0 When the patient's body or a part of the patient's body, such as the head, knees, torso, etc., is positioned in the static magnetic field B 0 Internally, the nuclear spins associated with the hydrogen nuclei that form water within the patient's tissue become polarized. The magnetic moments associated with these nuclear spins align along the magnetic field direction and produce a small net tissue magnetization in the magnetic field direction. The MRI system additionally includes magnetic gradient coils that produce spatially varying magnetic fields of smaller magnitude relative to the magnitude of the uniform magnetic field produced by the superconducting magnet. The spatially varying magnetic fields are configured to be orthogonal to each other in order to spatially encode a body part of interest within the patient by generating a characteristic resonant frequency for hydrogen nuclei at the part. The MRI system then transmits RF pulses using a Radio Frequency (RF) coil device at a frequency substantially corresponding to the characteristic resonance frequency of the hydrogen nuclei to generate an RF magnetic field B 1 . The energy of the RF pulse is absorbed by the hydrogen nuclei, thereby adding energy to the nuclear spins and adjusting the hydrogen nuclei from a stationary state to an excited state. When the hydrogen nuclei relax from the excited state back to the stationary state, the hydrogen nuclei in turn release the absorbed energy in the form of electromagnetic waves, i.e. Magnetic Resonance (MR) signals. The MR signals may be detected by the RF coil device and converted into images by a computer using known reconstruction algorithms.
In general, an RF coil apparatus transmits RF pulses through a transmitting coil arrangement and detects MR signals emitted by a patient's body through a receiving coil arrangement, in which a birdcage coil as at least a part of the receiving coil arrangement has a plurality of conductors, but the plurality of conductors are arranged substantially parallel and straight to each other, and one or more electronic components may be provided on each conductor, in which case an image generated based on the MR signals received by the receiving coil arrangement will exhibit brightness non-uniformity of very bright middle and very dark sides when the MRI system has a high magnetic field strength of 3T (units: tesla) or more.
In addition, conventional birdcage coils require the use of numerous electronic components to remove the electromagnetic coupling between the receive coil arrangement and the transmit coil arrangement if desired, such electronic components including decoupling circuits with PIN diodes whose switching speeds need to be sufficiently massive and which need to withstand large currents, the decoupling circuits being required to resonate to the operating frequency of the MRI system, i.e. the characteristic resonant frequency of the hydrogen nuclei, and an excessive number of decoupling circuits can reduce the Q value of the receive coil arrangement, thereby reducing image quality.
Disclosure of Invention
It is an object of the present application to provide a receiving coil arrangement for magnetic resonance imaging and a magnetic resonance imaging system, which are structurally elegant and which can significantly improve the quality of images generated by the magnetic resonance imaging system.
According to one aspect of the present application, there is provided a receive coil arrangement for magnetic resonance imaging comprising: a first end conductor and a second end conductor opposite the first end conductor, the first end conductor and the second end conductor together defining at least a portion of a cylindrical surface; a plurality of first capacitances and a plurality of second capacitances, the plurality of first capacitances dividing the first end conductor into a plurality of first ring segments, and the plurality of second capacitances dividing the second end conductor into a plurality of second ring segments; a plurality of decoupling circuits alternately connected in parallel to a corresponding one of the plurality of first capacitances and the plurality of second capacitances in a circumferential direction of the cylindrical surface, respectively; and a plurality of first intermediate conductors arranged in sequence in a circumferential direction of the cylindrical surface, at least a portion of each first intermediate conductor having a first spiral shape with respect to the cylindrical surface, and each first intermediate conductor including a first end and a second end, the first end of each first intermediate conductor being connected to a respective one of the first ring segments, and the second end of each first intermediate conductor being connected to a respective one of the second ring segments corresponding to the respective one of the first ring segments.
Optionally, the first end conductor, the second end conductor, the plurality of first capacitances, the plurality of second capacitances, the plurality of decoupling circuits, and the plurality of first intermediate conductors are disposed together on a first arch-shaped sheet of magnetic resonance-compatible electrically insulating material, wherein the first end conductor and the second end conductor together define a portion of a cylindrical surface; or wherein the first end conductor, the second end conductor, the plurality of first capacitances, the plurality of second capacitances, the plurality of decoupling circuits, and the plurality of first intermediate conductors are disposed together on at least two second arcuate blades made of a magnetic resonance compatible electrically insulating material and of complementary shape, the at least two second arcuate blades being detachably engaged by means of a snap-fit structure, wherein the first end conductor and the second end conductor together define a complete cylindrical surface.
Optionally, the receive coil arrangement for magnetic resonance imaging further comprises a plurality of second intermediate conductors arranged in sequence in a circumferential direction of the cylindrical surface, each second intermediate conductor being adjacent to a respective one of the first intermediate conductors, a portion of each second intermediate conductor having a second spiral shape with respect to the cylindrical surface, and each second intermediate conductor comprising a first end and a second end, the first end of each second intermediate conductor being connected to a respective one of the first ring segments and the second end of each second intermediate conductor being connected to a respective one of the second ring segments such that each second intermediate conductor, a respective one of the first intermediate conductors, a respective one of the first ring segments, and a respective one of the second ring segments together form an electrical circuit, wherein each first intermediate conductor electrically-insulatively intersects the respective one of the second intermediate conductors such that the electrical circuit defines a first region and a second region of equal area.
Optionally, no electronic component is provided on each first intermediate conductor; and/or no electronic components are provided on each of the second intermediate conductors.
Optionally, the first helix angle formed by the first helix shape relative to a generatrix of the cylindrical surface is in the range of 20 ° to 45 °, the second helix angle formed by the second helix shape relative to a generatrix of the cylindrical surface is in the range of 20 ° to 45 °, and the first helix angle and the second helix angle are the same or different.
Optionally, each first intermediate conductor and each second intermediate conductor comprises a first segment, a second segment, and a third segment connecting the first segment and the second segment, the first segment and the second segment of each first intermediate conductor having a first helical shape relative to the cylindrical surface, the first segment and the second segment of each second intermediate conductor having a second helical shape relative to the cylindrical surface, and the third segment of each first intermediate conductor intersecting the third segment of a respective one of the second intermediate conductors in electrical isolation.
Optionally, a portion of the third section of the first intermediate conductor overlaps a portion of the third section of a respective one of the second intermediate conductors in a radial direction of the cylindrical surface, wherein a width of the portion of the third section of the first intermediate conductor is smaller than a width of the remaining portion of the first intermediate conductor, and a width of the portion of the third section of the second intermediate conductor is smaller than a width of the remaining portion of the second intermediate conductor; and/or wherein the thickness of the portion of the third section of the first intermediate conductor is less than the thickness of the remaining portion of the first intermediate conductor and the thickness of the portion of the third section of the second intermediate conductor is less than the thickness of the remaining portion of the second intermediate conductor.
Optionally, the portion of the third section of the first intermediate conductor is separated from the portion of the third section of the respective one of the second intermediate conductors by a magnetic resonance compatible electrically insulating material in a radial direction of the cylindrical surface.
Optionally, a first additional capacitance is provided on a respective one of the first ring segments between the first end of each first intermediate conductor and the first end of a respective one of the second intermediate conductors, and a second additional capacitance is provided on a respective one of the second ring segments between the second end of each first intermediate conductor and the second end of a respective one of the second intermediate conductors.
Optionally, according to another aspect of the present application, there is provided a magnetic resonance imaging system comprising: a data acquisition device; and a radio frequency coil apparatus including the above-described receiving coil device and configured to operate in a receiving mode, wherein the radio frequency coil apparatus further includes a transmitting coil device including a first interface cable, the receiving coil device transferring the received magnetic resonance signal to the transmitting coil device through electromagnetic mutual inductance when the radio frequency coil apparatus operates in the receiving mode, and the transmitting coil device being electrically connected to the data acquisition device through the first interface cable to transfer the magnetic resonance signal received from the receiving coil device and the magnetic resonance signal received directly by the transmitting coil device itself to the data acquisition device; or wherein the receive coil arrangement further comprises a second interface cable through which the receive coil arrangement is electrically connected to the data acquisition arrangement for transferring magnetic resonance signals received by the receive coil arrangement to the data acquisition arrangement when the radio frequency coil apparatus is operated in the receive mode.
The receiving coil device and the magnetic resonance imaging system for magnetic resonance imaging, provided by the application, lengthen the lengths of the first intermediate conductor and the selective second intermediate conductor by enabling the first intermediate conductor and the selective second intermediate conductor to be spiralized, so that the inductance of the receiving coil device is increased, the capacitance of the receiving coil device is reduced, the difficulty of removing electromagnetic coupling between the receiving coil device and the transmitting coil device is reduced, and the uniformity of image brightness is improved. Furthermore, the receiving coil arrangement and the magnetic resonance imaging system for magnetic resonance imaging provided by the application remove the electromagnetic coupling of the receiving coil arrangement and the transmitting coil arrangement from the structure and significantly reduce the number of components, in particular decoupling circuits, that need to be used, and do not have to pay attention to whether the decoupling circuits resonate to the operating frequency of the MRI system or not and to the switching speed of the PIN diodes. In other words, the receive coil arrangement and the magnetic resonance imaging system provided by the present application also have two important functions, namely, removing electromagnetic coupling between the receive coil arrangement and the transmit coil arrangement when the radio frequency coil device is operated in the transmit mode and improving the homogeneity of the radio frequency magnetic field generated by the receive coil arrangement when the radio frequency coil device is operated in the receive mode, thereby improving the quality of the image generated by the magnetic resonance imaging system.
Other features of the present application and its advantages will become apparent from the following detailed description of exemplary embodiments of the present application, which proceeds with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description, serve to explain the principles of the application.
FIG. 1 is a schematic diagram of an exemplary MRI system.
Fig. 2 is a schematic perspective view of a receive coil arrangement for MRI according to one embodiment of the present application.
Fig. 3 is a schematic plan view of the receiving coil device of fig. 2 after being flattened in the circumferential direction of the cylindrical surface.
Fig. 4 is a schematic perspective view of a receive coil arrangement for MRI according to another embodiment of the present application.
Fig. 5 is a schematic plan view of the receiving coil device of fig. 4 after being flattened in the circumferential direction of the cylindrical surface.
Fig. 6 is another schematic plan view of the receiving coil apparatus of fig. 4 after flattening in the circumferential direction of the cylindrical surface to show the current state in the electrical loop of the receiving coil apparatus when the RF coil device is operated in the transmit mode.
Fig. 7 is another schematic plan view of the receiving coil apparatus of fig. 4 after flattening in the circumferential direction of the cylindrical surface to show the current state in the electrical loop of the receiving coil apparatus when the RF coil device is operated in the receiving mode.
Fig. 8 is a schematic plan view of a receiving coil device for MRI according to still another embodiment of the present application after flattening in the circumferential direction of the cylindrical surface.
Detailed Description
Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless it is specifically stated otherwise.
Techniques and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the specification where appropriate.
In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of exemplary embodiments may have different values.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.
Referring to fig. 1, fig. 1 generally illustrates an exemplary MRI system 10. The MRI system 10 comprises superconducting field magnet means 12, gradient coil means 13, RF coil apparatus comprising receiving coil means 14 and transmitting coil means 15, transmit/receive (T/R) switch 20, RF drive means 22, gradient coil drive means 23, data acquisition means 24, control means 25, and patient table or couch 26, etc.
Herein, the receive coil arrangement 14 may include, but is not limited to, a birdcage coil, variants thereof, etc., while the transmit coil arrangement 15 may include, but is not limited to, a volume coil, variants thereof, etc., as shown in fig. 1, the transmit coil arrangement 15 being fixedly attached to the gradient coil arrangement 13, in contrast to the receive coil arrangement 14 being relatively smaller and relatively independent, which may be more frequently and easily replaced during the lifetime of the MRI system 10.
During scanning of a body part of interest of a subject 16 (e.g., a patient) with the MRI system 10 to image its anatomy, first, the receive coil arrangement 14 is worn or placed adjacent at the body part of interest of the subject 16 (including but not limited to the head, torso, knee, etc. of the subject 16), and then the body part of interest is positioned by means of the patient table or couch 26 into an imaging region 18 enclosed by the field magnet arrangement 12, the gradient coil arrangement 13, and the transmit coil arrangement 15, the imaging region 18 forming an imaging channel having a channel axis parallel to the z-axis, generally in the imaging region 18, the receive coil arrangement 14 and the transmit coil arrangement 15 are close to each other so as to be electromagnetically transformable. Then, a static magnetic field B is formed in the imaging region 18 by the superconducting magnet device 12 0 In which the transmitting coil means 15 transmits electromagnetic waves in the form of RF pulses to a body part of interest, thereby generating a high-frequency magnetic field B 1 + This excites the body part of interest in the different slices to be imagedThen the receiving coil means 14 and/or the transmitting coil means 15 receive in the form of MR signals electromagnetic waves generated when the proton spins excited in the different slices to be imaged return to alignment with the initial magnetization vector, i.e. the MR signals form a further high-frequency magnetic field B in the receiving coil means 14 and/or the transmitting coil means 15 1 — Wherein the spatially varying magnetic field formed in the imaging region 18 by the gradient coil arrangement 13 under the drive of the gradient coil drive 23 frequency encodes MR signals from different slices to be imaged.
During scanning, the RF coil apparatus may be divided into operating in a receive mode and in a transmit mode. For example, the transmit coil arrangement 15 may comprise a first interface cable 15a arranged between the volume coil and the data acquisition arrangement 24, and when operating in the receive mode, the T/R switch 20 may selectively electrically connect only the transmit coil arrangement 15 to the data acquisition arrangement 24 by means of the first interface cable 15a, based on control signals from the control arrangement 25, and in this case there may be no physical connection between the receive coil arrangement 14 and the transmit coil arrangement 15 and no provision of a further interface cable for the receive coil arrangement 14, MR signals received by the receive coil arrangement 14 from the body part of interest of the subject 16 may be transferred to the transmit coil arrangement 15 by electromagnetic mutual inductance, and the transmit coil arrangement 15 transfers MR signals from the receive coil arrangement 14 and MR signals directly from the body part of interest of the subject 16 in combination to the data acquisition arrangement 24. In other words, in the receiving mode, it is desirable that the receiving coil device 14 and the transmitting coil device 15 are electromagnetically coupled and resonate together at the larmor frequency of protons, which is based on the static magnetic field B 0 Is determined by the intensity of (a). Alternatively, the receive coil arrangement 14 may comprise a second interface cable 14a arranged between the surface coil and the data acquisition device 24, in which case the T/R switch 20 may selectively electrically connect only the receive coil arrangement 14 to the data acquisition device 24 by means of the second interface cable 14a for directly acquiring MR signals from the body part of interest of the subject 16 via the receive coil arrangement 14. Alternatively, the method comprisesThe T/R switch 20 may electrically connect both the transmit coil arrangement 15 and the receive coil arrangement 14 to the data acquisition arrangement 24, if desired. When operating in the transmit mode, the T/R switch 20 may electrically connect the transmit coil arrangement 15 to the RF drive arrangement 22 based on a control signal from the control arrangement 25, so that the RF drive arrangement 22 may send signals related to RF pulses to the transmit coil arrangement 15, and in this case the receive coil arrangement 14 should be decoupled from and not resonate with the transmit coil arrangement 15 to improve imaging quality. The receiver coil arrangement 14 and the transmitter coil arrangement 15 are therefore structurally independent of one another but are in close proximity to one another during operation and can be electromagnetically coupled or decoupled from one another if desired.
Now, how the receiving coil apparatus 14 according to one embodiment of the present application improves the quality of an image generated by the exemplary MRI system 10 by structural improvement will be described with reference to fig. 2, the exemplary receiving coil apparatus 14 including: the first end conductor 28 and the second end conductor 30 opposite the first end conductor 28, the first end conductor 28 and the second end conductor 30 together defining at least a portion of a cylindrical surface, although as shown in fig. 2, the first end conductor 28 and the second end conductor 30 each form a complete loop to define a complete cylindrical surface, alternatively, depending on the particular application, the first end conductor 28 and the second end conductor 30 may each form a portion of a loop to define a portion of a cylindrical surface, i.e., an arcuate surface having an arcuate perimeter with a length less than the length of the circular perimeter of the complete cylindrical surface. Here, the cylindrical surface has a central axis passing through the center of the complete ring formed by the first end conductor 28 and the second end conductor 30, or alternatively through the center of the complete ring imaginary on the basis of the part of the ring formed by the first end conductor 28 and the second end conductor 30, and also has a generatrix parallel to the central axis, a circumferential direction along the circular circumference of the cross section of the cylindrical surface, and a radial direction perpendicular to the central axis; a plurality of first capacitances (e.g., first capacitances 32a, 32 b) dividing, e.g., equally dividing, the first end conductor 28 into a plurality of first ring segments (e.g., first ring segments 28a, 28 b) and a plurality of second capacitances (e.g., second capacitances 34a, 34 b) dividing, e.g., equally dividing, the second end conductor 30 into a plurality of second ring segments (e.g., second ring segments 30a, 30 b) equal in number to the number of first ring segments, e.g., 8 in the case where the first end conductor 28 and the second end conductor 30 define a complete cylindrical surface as shown in fig. 2; a plurality of decoupling circuits (e.g., as shown in fig. 3, decoupling circuits 36a, 36 b) equal in number to the plurality of first ring segments, e.g., 8 in number, each of the plurality of decoupling circuits being configured, for example, as a passive decoupling circuit, including serially connected inductors 38a, 38b and PIN diodes 40a, 40b (as shown in fig. 3), and being alternately connected in parallel with a respective one of the plurality of first and second capacitances in a circumferential direction of the cylindrical surface, respectively, such as in particular in the receiver coil device 14 shown in fig. 3 after the cylindrical surface is flattened in the circumferential direction, one of the plurality of decoupling circuits 36a is first connected in parallel with the respective one of the first capacitances 32a, and then the other one of the plurality of decoupling circuits 36b is alternately connected in parallel with the respective one of the second capacitances 34b as proceeding in the circumferential direction of the cylindrical surface to encounter the next capacitance; and a plurality of first intermediate conductors (e.g., first intermediate conductors 44) arranged sequentially, e.g., equidistantly, in the circumferential direction of the cylindrical surface, at least a portion of each first intermediate conductor 44 having a first spiral shape with respect to the cylindrical surface, and the number of the plurality of first intermediate conductors being equal to the number of the plurality of first ring segments, e.g., 8, to more efficiently utilize the surface area of the cylindrical surface to arrange the plurality of first intermediate conductors, herein, "conductors" refer to electrical conductors, e.g., may be made of copper, and the surface of copper is coated with an antioxidant material.
Returning to fig. 2, for example, the first intermediate conductors 44, which are elongated, thin, and optionally have a first helical shape overall, include first ends 44a and second ends 44b, the first end 44a of each first intermediate conductor 44 being connected to a respective one of the first ring segments 28b, and the second end 44b of each first intermediate conductor 44 being connected to a respective one of the second ring segments 30b corresponding to a respective one of the first ring segments 28 b. In addition, no electronic component is arranged on each first intermediate conductor, so that structural simplicity is improved.
Such a receiving coil arrangement 14 achieves decoupling from the transmitting coil arrangement 15 in the transmitting mode of the RF coil apparatus by means of the plurality of first capacitances 32a, 32b, the plurality of second capacitances 34a, 34b, and the plurality of decoupling circuits 38a, 38 b.
In contrast, in the prior art, a conventional birdcage coil as at least part of the receive coil arrangement has a plurality of conductors, but the plurality of conductors are arranged substantially parallel to each other and straight parallel to the central axis of the cylindrical surface, and one or more electronic components (e.g., capacitors) may also be provided on each conductor, in which case, when the MRI system has a high magnetic field strength of 3T or more, the image generated based on the MR signals received by the receive coil arrangement will exhibit brightness non-uniformities that are very bright in the middle and very dark on both sides. Whereas the receiving coil device 14 shown in fig. 2 lengthens the length of the first intermediate conductors by spiraling the plurality of first intermediate conductors such that the inductance of the receiving coil device 14 increases and the capacitance decreases, thereby reducing the difficulty of decoupling between the receiving coil device 14 and the transmitting coil device 15 and improving uniformity of image brightness.
Now, the receiving coil device 14 according to another embodiment of the present application will be described with reference to fig. 4 and 5, as shown, in addition to the first intermediate conductors 44 that are elongated, thin, and partially (also may be integrally) have a first spiral shape, the receiving coil device 14 further includes a plurality of second intermediate conductors (e.g., second intermediate conductors 46) that are sequentially, e.g., equidistantly, arranged in the circumferential direction of the cylindrical surface, each second intermediate conductor 46 being adjacent to a corresponding one of the first intermediate conductors 44, a portion of each second intermediate conductor 46 having a second spiral shape with respect to the cylindrical surface, and the number of the plurality of second intermediate conductors being equal to the number of the plurality of first ring segments, e.g., 8, to more efficiently utilize the surface area of the cylindrical surface to arrange the plurality of first intermediate conductors and the plurality of second intermediate conductors.
For example, the second intermediate conductors 46 include first ends 46a and second ends 46b, the first end 46a of each second intermediate conductor 46 being connected to a respective one of the first ring segments 28b, and the second end 46b of each second intermediate conductor 46 being connected to a respective one of the second ring segments 30b corresponding to a respective one of the first ring segments 28 b. In addition, no electronic components are provided on each of the second intermediate conductors 46, nor are electronic components provided, to improve structural simplicity.
Each first intermediate conductor 44, a respective one of the first intermediate conductors 46, a respective one of the first ring segments 28B, and a respective one of the second ring segments 30B together form an electrical circuit, wherein the first intermediate conductors 44 electrically-insulatively intersect the second intermediate conductors 46 such that the electrical circuit defines first and second regions a, B (as shown in fig. 5) of equal area, i.e., the electrical circuit forms a shape similar to an inclined arabic numeral 8.
In more detail, with continued reference to fig. 4 and 5, each of the first intermediate conductors 44 and the respective one of the second intermediate conductors 46 includes a first segment 44c, 46c, a second segment 44d, 46d, and a third segment 44e, 46e connecting the first segment 44c, 46c and the second segment 44d, 46d, the first segment 44c and the second segment 44d of each of the first intermediate conductors 44 extending at a first helix angle with respect to a generatrix of the cylindrical surface to form a first helical shape and being spaced apart in a circumferential direction of the cylindrical surface, and similarly the first segment 46c and the second segment 46d of the second intermediate conductor 46 extending at a second helix angle with respect to the generatrix of the cylindrical surface to form a second helical shape and being spaced apart in the circumferential direction of the cylindrical surface, such that the third segment 44e of the first intermediate conductor 44 and the third segment 46e of the second intermediate conductor 46 may electrically intersect at an opposite angle with respect to the central axis of the cylindrical surface, a portion of the third segment 44e of the first intermediate conductor 44 and a portion of the third intermediate conductor 46 may be referred to as a third intermediate segment 46 overlapping a first portion of the second intermediate conductor 46 and a second intermediate segment 46 overlapping a second intermediate segment 46 at a second intermediate segment 46 in the radial direction, in other words the first intermediate segment 46.
For example, as shown in fig. 5, the first helix angle α formed by the first helix shape relative to the generatrix L of the cylindrical surface may range from 20 ° to 45 °, such as about 22.5 °, alternatively the second helix angle β formed by the second helix shape relative to the generatrix L of the cylindrical surface may range from 20 ° to 45 °, such as about 22.5 °, and the first helix angle α and the second helix angle β may be the same or different. Alternatively, the first/second helix angles α/β may vary for different first/second intermediate conductors and different segments of the same first/second intermediate conductors. In this context, the helix angle may be defined as the angle formed by the first/second sections 44c, 46c/44d, 46d, which change from helical to inclined after flattening in the circumferential direction of the cylindrical surface, with respect to the generatrix of the cylindrical surface.
The features of the receiver coil arrangement 14 not shown in fig. 4 in other respects may be identical to those described above with respect to the receiver coil arrangement 14 shown in fig. 2.
Optionally, the overlapping point of the first intermediate conductor 44 and the overlapping point of the second intermediate conductor 46 are separated in the radial direction of the cylindrical surface by a magnetic resonance compatible electrically insulating material (not shown).
In addition, since the distributed capacitance formed between the overlapping point of the first intermediate conductor 44 and the overlapping point of the second intermediate conductor 46 may affect the image quality, it is desirable to reduce the distributed capacitance by the third section 44e of the first intermediate conductor 44 and the third section 46e of the second intermediate conductor 46 which are specifically designed. Equation (1) for the distributed capacitance is as follows:
C ＝ ε 0 ×ε r ×A / d (1)
wherein, C represents the distributed capacitance formed by overlapping the conductors;
ε 0 and epsilon r Represent the dielectric constant, determined by the insulating material;
a represents the area of each conductor overlapping portion; and
d represents the distance between the conductors.
Alternatively, not shown but as a variant, the width of the third section 44e of the first intermediate conductor 44 on the cylindrical surface is smaller than the widths of the first section 44c and the second section 44d of the first intermediate conductor 44, and the width of the third section 46e of the second intermediate conductor 46 is smaller than the widths of the first section 46c and the second section 46d of the second intermediate conductor 46. Specifically, the third section 44e/46e of the first/second intermediate conductor 44/46 includes a first connection end connected to the first section 44c/46c and a second connection end connected to the second section 44d/46d, and the overlapping point of the first/second intermediate conductor 44/46 is located between the first connection end and the second connection end, so that the width of the first/second intermediate conductor 44/46 gradually narrows from the first connection end or the second connection end toward the overlapping point. Alternatively, the width of the first/second intermediate conductors 44/46 may also be tapered near the overlap point to ensure that the width of the overlap point of the first/second intermediate conductors 44/46 is less than the width of the remainder of the first intermediate conductors 44.
Alternatively, not shown but as a modification, the thickness of the third section 44e of the first intermediate conductor 44 in the radial direction of the cylindrical surface is smaller than the thicknesses of the first section 44c and the second section 44d of the first intermediate conductor 44, and the thickness of the third section 46e of the second intermediate conductor 46 is smaller than the thicknesses of the first section 46c and the second section 46d of the second intermediate conductor 46. Specifically, the thickness of the first/second intermediate conductors 44/46 becomes gradually thinner from the first connection end or the second connection end toward the overlapping point. Alternatively, the thickness of the first/second intermediate conductors 44/46 may also be made to taper sharply around the overlap point to ensure that the thickness of the overlap point of the first/second intermediate conductors 44/46 is less than the thickness of the remainder of the first intermediate conductor 44. The reduced thickness at the overlap point of the first/second intermediate conductors 44/46 may be such that the overlap point of the first intermediate conductor 44 and the overlap point of the second intermediate conductor 46 are separated by a gap in the radial direction of the cylindrical surface, which may optionally be filled with a magnetic resonance compatible electrically insulating material. In addition, the overlapping point of the first intermediate conductor 44 or the overlapping point of the second intermediate conductor 46 may also be radially outward or inward in the radial direction of the cylindrical surface than the remainder of the first intermediate conductor 44 or the remainder of the second intermediate conductor 46 to ultimately achieve the desired distributed capacitance.
Alternatively, the angle at which the first intermediate conductor 44 and the second intermediate conductor 46 electrically insulated from each other is 90 degrees, i.e., the third section 44e of the first intermediate conductor 44 and the third section 46e of the second intermediate conductor 46 are orthogonal to each other, to minimize the area of overlap between the overlapping point of the first intermediate conductor 44 and the overlapping point of the second intermediate conductor 46.
In fig. 6 and 7, the principle of decoupling the receiver coil arrangement 14 from the transmitter coil arrangement 15 is illustrated by way of example in fig. 4 in which the receiver coil arrangement 14 is formed by a partially spiral-shaped first intermediate conductor 44 and second intermediate conductor 46 together with a respective one of the first ring segments 28b and a respective one of the second ring segments 30 b. First, during scanning a body part of interest of an object 16 with the MRI system 10, the receiving coil arrangement 14 is arranged adjacently with respect to the transmitting coil arrangement 15 such that the central axis of the cylindrical surface is parallel to the channel axis of the imaging channel, in which case the normal direction of the surfaces of the first and second regions a, B is parallel to the static magnetic field B 0 Perpendicular to the direction of (a) or the surfaces of the first region A and the second region B and the static magnetic field B 0 Is parallel to the direction of the (c). Meanwhile, when the RF coil apparatus is operated in the transmit mode, the entire RF magnetic field B emitted by the transmit coil arrangement 15 1 + Or the whole RF magnetic field B 1 + A part of the components of (a) will extend parallel to the normal direction of the surfaces of the first and second regions a, B, e.g. the whole RF magnetic field B as shown in fig. 6 1 + Or the whole RF magnetic field B 1 + A part of the components of (a) extend inward perpendicular to the paper surface, and alternately all of the RF magnetic fields B 1 + Or the whole RF magnetic field B 1 + It is also possible that some of the components of (a) extend outwards perpendicular to the plane of the paper. Based on faraday's law of electromagnetic induction, a first current is simultaneously induced in the electrical circuit, in particular in the first intermediate conductor 44 forming the electrical circuitI 1 And a second current I 2 Since the areas of the first area A and the second area B are equal, the induced first current I 1 And a second current I 2 Will be equal in magnitude and opposite in direction, so that the first current I 1 And a second current I 2 The same first current I will similarly occur in the second intermediate conductor 46 forming the circuit 1 And a second current I 2 The phenomena cancel each other, thereby causing decoupling between the receive coil arrangement 14 and the transmit coil arrangement 15. In addition, since the transmitting coil device 15 transmits the RF magnetic field B in the transmitting mode 1 + A large current is induced in the receive coil means 14 such that the PIN diode in the decoupling circuit is turned on and the inductance in the decoupling circuit forms a parallel resonant circuit with the capacitance, thereby creating a large impedance such that an open circuit is formed between the second intermediate conductor 46 and the first intermediate conductor 44, which are spaced adjacent to the capacitance, i.e. the electrical connection between the two is broken, to further facilitate decoupling between the receive coil means 14 and the transmit coil means 15. While when the RF coil device is operated in the receive mode, an induced current is generated in the electrical loop by electromagnetic waves, i.e. MR signals, emitted from the body part of interest of the subject 16, e.g. a third current I is induced in the first intermediate conductor 44 as shown in fig. 7 3 And a fourth current I is induced in the second intermediate conductor 46 4 Based on the reciprocity theorem (the principle of reciprocity), a third current I 3 And a fourth current I 4 Will simultaneously generate RF magnetic field B 1 — All RF magnetic fields B 1 — Or the whole RF magnetic field B 1 — A part of the component of (a) extends parallel to the normal direction of the surfaces of the first and second regions A, B, and a third current I due to the electrically insulating intersection of the third section 44e of the first intermediate conductor 44 with the third section 46e of the second intermediate conductor 46 3 And a fourth current I 4 Will cross-flow in the direction of the central axis of the cylindrical surface to increase the RF magnetic field B 1 — Is a uniform property of (a). In addition, since the MR signals received by the receiving coil device 14 in the receiving mode induce a small current in the receiving coil device 14The PIN diode in the coupling circuit is not turned on, i.e. the decoupling circuit is not operational.
Merely to explain the principle, the reciprocity theorem mentioned herein relates to the following formula (2):
where ε represents the induced electromotive force generated in the receive coil arrangement 14, i.e. the MR signals received by the receive coil arrangement 14 from the body part of interest of the subject when the RF coil device is operated in the receive mode;
m represents the magnetization of the sample;
B 1 The RF magnetic field generated when the RF coil apparatus having a function of receiving MR signals, which is constituted by the selective transmitting coil device 15 and the receiving coil device 14, passes through a unit current at the magnetization M is shown.
Thus, by providing a plurality of Arabidopsis thaliana 8 shaped electrical loops, the receive coil arrangement 14 has two important functions, namely to achieve decoupling between the receive coil arrangement 14 and the transmit coil arrangement 15 when operating in a transmit mode and to increase the radio frequency magnetic field B generated by the receive coil arrangement 14 when operating in a receive mode 1 — Thereby improving image quality.
It will be appreciated that all components used in the receive coil arrangement 14, including but not limited to the first plurality of capacitors, the second plurality of capacitors, and the decoupling circuits just mentioned, must be non-magnetic, and that the first plurality of capacitors and the second plurality of capacitors are high voltage tolerant and have high Q values.
In contrast, in the prior art, a conventional birdcage coil as at least a part of the receive coil arrangement requires the use of a large number of components to achieve decoupling of the receive coil arrangement from the transmit coil arrangement, wherein the switching speed of the PIN diode needs to be sufficiently large (e.g. about 70 ns) and needs to withstand a large current (e.g. up to 1A), the decoupling circuit needs to resonate to the operating frequency of the MRI system, i.e. the larmor frequency mentioned above, and too many decoupling circuits would reduce the Q value of the receive coil arrangement, reducing the imaging quality. The receiving coil arrangement 14 provided by the present application, however, significantly reduces the number of components, in particular decoupling circuits, that need to be used by structurally implementing decoupling of the receiving coil arrangement 14 from the transmitting coil arrangement 15, without concern for whether the decoupling circuits resonate to the operating frequency of the MRI system 10 and without concern for the switching speed of the PIN diodes.
Alternatively, a further embodiment of the receiving-coil arrangement 14 is shown in fig. 8, wherein additionally a first additional capacitance 33 is arranged on the respective one of the first ring segments 28b between the first ends 44a, 46a of each of the first intermediate conductors 44 and the respective one of the second intermediate conductors 46, and a second additional capacitance 35 is arranged on the respective one of the second ring segments 30b between the second ends 44b, 46b of each of the first intermediate conductors 44 and the respective one of the second intermediate conductors 46.
Alternatively, returning to fig. 4, variations on the design of the plurality of first/second intermediate conductors may also be made based on the principle that the electrical circuit defines a first region a and a second region B of equal area. For example, the lengths of the first/second sections 44c/44d of the at least one first intermediate conductor 44 and the first/second sections 46c/46d of the at least one second intermediate conductor 46 may be greater than the lengths of the second/sections 44d/44c of the at least one first intermediate conductor 44 and the second/sections 46d/46c of the at least one second intermediate conductor 46, respectively, and accordingly, the spacing between the first/second ends 44a/44B of the first intermediate conductor 44 and the first/second ends 46a/46B of the second intermediate conductor 46 will be less than the spacing between the second/ends 44B/44a of the first intermediate conductor 44 and the second/ends 46B/46a of the second intermediate conductor 46 such that the area of the first region a is equal to the area of the second region B.
Further optionally, the first end conductor 28, the second end conductor 30, the plurality of first capacitances 32a, 32b, the plurality of second capacitances 34a, 34b, the plurality of decoupling circuits 38a, 38b, the plurality of first intermediate conductors, the plurality of second intermediate conductors, and optionally the plurality of first additional capacitances 33 and the plurality of second additional capacitances 35 are disposed together on at least two second arcuate sheets 50a, 50b (shown in fig. 2) made of a magnetic resonance compatible electrically insulating material and of complementary shape, the at least two second arcuate sheets 50a, 50b being detachably joined by means of a snap-fit structure, wherein the first end conductor 28 and the second end conductor 30 together define one complete cylindrical surface. Thus, when the receiving coil device 14 is worn or placed adjacently at a body part of interest of a subject, the body part of interest of the subject may be placed in one of the at least two second arch-shaped sheets 50a, 50b first, and then the remaining second arch-shaped sheets 50b of the at least two second arch-shaped sheets 50a, 50b are joined to the one of the second arch-shaped sheets 50a to facilitate the wearing and placement of the receiving coil device 14.
It will be appreciated that for such a split design of the at least two second arched-shaped bodies 50a, 50b, for example, at least one first cutting surface comprising the central axis of the cylindrical surface and flat may be imagined, which would cut only to at least two first ring segments and at least two second ring segments corresponding (e.g. diametrically opposed) to the at least two first ring segments without cutting to the first capacitance, the second capacitance, the decoupling circuit, and the first and second intermediate conductors, to form the at least two second arched-shaped bodies 50a, 50b based on such cutting. When the at least two second arcuate sheets are joined together, the at least two first ring segments and the at least two second ring segments, which are cut, will respectively reform an electrical connection relationship.
In order to cut the at least one first cutting face only to the at least two first ring segments and the at least two second ring segments, a spacing between the first/second ends 44a/44b of the first intermediate conductor 44 and the first/second ends 46a/46b of the second intermediate conductor 46 may be adjusted, for example, a spacing between the first ends 44a of the first intermediate conductor 44 and the first ends 46a of the second intermediate conductor 46 in fig. 4 may be reduced and a spacing between the second ends 44b of the first intermediate conductor 44 and the second ends 46b of the second intermediate conductor 46 may be enlarged such that a spacing between the first ends 44a of the first intermediate conductor 44 and the second ends 44b of the first intermediate conductor 44 in a circumferential direction of the cylindrical surface is reduced, thereby cutting the at least one first cutting face. Meanwhile, in order to ensure that the area of the first region a is equal to the area of the second region B, the overlapping point of the first intermediate conductor 44 and the overlapping point of the second intermediate conductor 46 may be closer to the second ring segment 30B, and/or the lengths of the first section 44c of the first intermediate conductor 44 and the first section 46c of the second intermediate conductor 46 may be greater than the lengths of the second section 44c of the first intermediate conductor 44 and the second section 46c of the second intermediate conductor 46.
Additionally or alternatively, a second cut surface may be imagined that forms a curved or folded cut line on the cylindrical surface to form the at least two second arched-shaped sheets 50a, 50b based on this cutting pattern as shown by the dashed lines in fig. 2, to avoid cutting to the first capacitor, the second capacitor, the decoupling circuit, and the first and second intermediate conductors.
Optionally, the first end conductor 28, the second end conductor 30, the plurality of first capacitances 32a, 32b, the plurality of second capacitances 34a, 34b, the plurality of decoupling circuits 38a, 38b, the plurality of first intermediate conductors, the plurality of second intermediate conductors, and optionally the plurality of first additional capacitances 33 and the plurality of second additional capacitances 35 are together disposed on one first arcuate sheet of magnetic resonance compatible electrically insulating material such that the first end conductor 28 forming part of the loop and the second end conductor 30 forming part of the loop together define a portion of a cylindrical surface. For example, the cross-section of the one first arcuate blade covers an angular range from 0 degrees to 360 degrees, preferably from 180 degrees to 360 degrees.
Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present application. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the present application. The scope of the application is defined by the appended claims.
Claims (10)
1. A receive coil arrangement (14) for magnetic resonance imaging, comprising:
a first end conductor (28) and a second end conductor (30) opposite the first end conductor (28), the first end conductor (28) and the second end conductor (30) together defining at least a portion of a cylindrical surface;
a plurality of first capacitances (32 a, 32 b) dividing the first end conductor (28) into a plurality of first ring segments and a plurality of second capacitances (34 a, 34 b) dividing the second end conductor (30) into a plurality of second ring segments;
a plurality of decoupling circuits (36 a, 36 b), the plurality of decoupling circuits (36 a, 36 b) being alternately connected in parallel to a respective one of the plurality of first capacitances and the plurality of second capacitances in a circumferential direction of the cylindrical surface, respectively; and
a plurality of first intermediate conductors (44) arranged in sequence in a circumferential direction of the cylindrical surface, at least a portion of each first intermediate conductor having a first spiral shape with respect to the cylindrical surface, and each first intermediate conductor including a first end (44 a) and a second end (44 b), the first end (44 a) of each first intermediate conductor (44) being connected to a respective one of the first ring segments, and the second end (44 b) of each first intermediate conductor (44) being connected to a respective one of the second ring segments corresponding to the respective one of the first ring segments.
2. The receive coil assembly (14) for magnetic resonance imaging of claim 1 wherein the first end conductor (28), the second end conductor (30), the plurality of first capacitances (32 a, 32 b), the plurality of second capacitances (34 a, 34 b), the plurality of decoupling circuits (36 a, 36 b), and the plurality of first intermediate conductors are disposed together on a first arcuate sheet of magnetic resonance compatible electrically insulating material, wherein the first end conductor (28) and the second end conductor (30) together define a portion of a cylindrical surface; or (b)
Wherein the first end conductor (28), the second end conductor (30), the plurality of first capacitances (32 a, 32 b), the plurality of second capacitances (34 a, 34 b), the plurality of decoupling circuits (36 a, 36 b) and the plurality of first intermediate conductors are together disposed on at least two second arcuate sheets of magnetic resonance compatible electrically insulating material and complementary shape, which are detachably joined by means of a snap-fit structure, wherein the first end conductor (28) and the second end conductor (30) together define one complete cylindrical surface.
3. The receive coil device (14) for magnetic resonance imaging according to claim 1 or 2, further comprising a plurality of second intermediate conductors arranged in sequence in a circumferential direction of the cylindrical surface, each second intermediate conductor (46) being adjacent to a respective one of the first intermediate conductors, a portion of each second intermediate conductor (46) having a second spiral shape with respect to the cylindrical surface, and each second intermediate conductor (46) comprising a first end (46 a) and a second end (46 b), the first end (46 a) of each second intermediate conductor (46) being connected to a respective one of the first ring segments and the second end (46 b) of each second intermediate conductor (46) being connected to a respective one of the second ring segments such that each second intermediate conductor, a respective one of the first intermediate conductors, a respective one of the first ring segments and a respective one of the second ring segments together form an electrical circuit,
Wherein each first intermediate conductor (44) electrically isolated intersects a corresponding one of the second intermediate conductors (46) such that the electrical circuit defines first (a) and second (B) regions of equal area.
4. A receive coil arrangement (14) for magnetic resonance imaging according to claim 3, characterized in that no electronic components are provided on each first intermediate conductor (44); and/or no electronic components are provided on each second intermediate conductor (46).
5. A receive coil arrangement (14) for magnetic resonance imaging according to claim 3 or 4, characterized in that the first helix angle formed by the first helix shape with respect to the generatrix of the cylindrical surface is in the range of 20 ° to 45 °, the second helix angle formed by the second helix shape with respect to the generatrix of the cylindrical surface is in the range of 20 ° to 45 °, and the first helix angle and the second helix angle are identical or different.
6. The receive coil device (14) for magnetic resonance imaging as set forth in any one of claims 3 to 5, characterized in that each first intermediate conductor (44) and each second intermediate conductor (46) comprises a first segment (44 c, 46 c), a second segment (44 d, 46 d) and a third segment (44 e, 46 e) connecting the first segment (44 c, 46 c) and the second segment (44 d, 46 d), the first segment and the second segment of each first intermediate conductor (44) having a first spiral shape with respect to a cylindrical surface, the first segment and the second segment of each second intermediate conductor (46) having a second spiral shape with respect to the cylindrical surface, and the third segment (44 e) of each first intermediate conductor (44) intersecting the third segment (46 e) of the respective one of the second intermediate conductors (46) in an electrically insulating manner.
7. The receive coil device (14) for magnetic resonance imaging as set forth in claim 6, characterized in that a portion of the third segment (44 e) of the first intermediate conductor (44) overlaps a portion of the third segment (46 e) of a respective one of the second intermediate conductors (46) in a radial direction of the cylindrical surface,
wherein the width of the portion of the third section (44 e) of the first intermediate conductor (44) is smaller than the width of the rest of the first intermediate conductor (44) and the width of the portion of the third section (46 e) of the second intermediate conductor (46) is smaller than the width of the rest of the second intermediate conductor (46); and/or
Wherein the thickness of the portion of the third section (44 e) of the first intermediate conductor (44) is smaller than the thickness of the remaining portion of the first intermediate conductor (44), and the thickness of the portion of the third section (46 e) of the second intermediate conductor (46) is smaller than the thickness of the remaining portion of the second intermediate conductor (46).
8. The receive coil device (14) for magnetic resonance imaging as set forth in claim 7, characterized in that the portion of the third segment (44 e) of the first intermediate conductor (44) is separated from the portion of the third segment (46 e) of the respective one of the second intermediate conductors (46) by a magnetic resonance compatible electrically insulating material in a radial direction of the cylindrical surface.
9. The receive coil device (14) for magnetic resonance imaging according to any one of claims 3 to 8, characterized in that a first additional capacitance (33) is arranged on a respective one of the first ring segments between the first end (44 a) of each first intermediate conductor (44) and the first end (46 a) of a respective one of the second intermediate conductors (46), and a second additional capacitance (35) is arranged on a respective one of the second ring segments between the second end (44 b) of each first intermediate conductor (44) and the second end (46 b) of a respective one of the second intermediate conductors (46).
10. A magnetic resonance imaging system (10), characterized by comprising:
a data acquisition device (24); and
radio frequency coil device comprising a receiving coil arrangement (14) according to any of claims 1 to 9 and configured to operate in a receiving mode,
wherein the radio frequency coil arrangement further comprises a transmit coil arrangement (15), the transmit coil arrangement (15) comprising a first interface cable (15 a), the receive coil arrangement (14) transferring received magnetic resonance signals to the transmit coil arrangement (15) by electromagnetic mutual inductance when the radio frequency coil arrangement is operated in the receive mode, and the transmit coil arrangement (15) being electrically connected to the data acquisition arrangement (24) by the first interface cable (15 a) for transferring magnetic resonance signals received from the receive coil arrangement (14) and magnetic resonance signals received directly by the transmit coil arrangement (15) itself to the data acquisition arrangement (24); or (b)
Wherein the receive coil arrangement (14) further comprises a second interface cable (14 a), the receive coil arrangement (14) being electrically connected to the data acquisition arrangement (24) via the second interface cable (14 a) for transferring magnetic resonance signals received by the receive coil arrangement (14) to the data acquisition arrangement (24) when the radio frequency coil device is operated in the receive mode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310116301.XA CN116482592A (en) | 2023-02-03 | 2023-02-03 | Receiving coil device for magnetic resonance imaging and magnetic resonance imaging system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310116301.XA CN116482592A (en) | 2023-02-03 | 2023-02-03 | Receiving coil device for magnetic resonance imaging and magnetic resonance imaging system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116482592A true CN116482592A (en) | 2023-07-25 |
Family
ID=87223889
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310116301.XA Pending CN116482592A (en) | 2023-02-03 | 2023-02-03 | Receiving coil device for magnetic resonance imaging and magnetic resonance imaging system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116482592A (en) |
-
2023
- 2023-02-03 CN CN202310116301.XA patent/CN116482592A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6396271B1 (en) | Tunable birdcage transmitter coil | |
| US9229076B2 (en) | Decoupling of multiple channels of an MRI RF coil array | |
| CN104067136B (en) | The multi-resonant T/R antennas generated for MR images | |
| EP1844348B1 (en) | Orthogonal coil for magnetic resonance imaging | |
| US7495443B2 (en) | RF coil system for super high field (SHF) MRI | |
| US5680047A (en) | Multipl-tuned radio frequency coil for simultaneous magnetic resonance imaging and spectroscopy | |
| US20040140808A1 (en) | RF coil for imaging system | |
| US20150054506A1 (en) | Magnetic Resonance Coil, Device and System | |
| US7239139B2 (en) | RF coil system for a magnetic resonance imaging apparatus | |
| JP2006507913A (en) | Degenerate cage coil, transmitter / receiver, and method thereof | |
| WO2010045457A2 (en) | Coil element decoupling for mri | |
| US20090009414A1 (en) | Antenna array | |
| CN209746108U (en) | Local coil for a magnetic resonance tomography apparatus | |
| WO2014068447A1 (en) | Z-segmented radio frequency antenna device for magnetic resonance imaging | |
| US11204401B2 (en) | Cylindrical-like single layer technology (SLT) magnetic resonance imaging (MRI) array coil with at least one row as a birdcage coil in transmit mode | |
| US10859647B2 (en) | Magnetic resonance imaging (MRI) transmit (Tx)/ receive (Rx) coil using the same array coil | |
| US5329233A (en) | Cylindrical local coil for nuclear magnetic resonance imaging | |
| US20080161675A1 (en) | Ultra-Short Mri Body Coil | |
| US5144239A (en) | Circularly polarizing rf antenna for an mri apparatus | |
| US10942233B2 (en) | Multi-turn magnetic resonance imaging (MRI) array coil with ring decoupling for improved coil isolation | |
| RU183997U1 (en) | MAGNETIC RESONANT TOMOGRAPH RADIO FREQUENCY COIL | |
| CN116482592A (en) | Receiving coil device for magnetic resonance imaging and magnetic resonance imaging system | |
| CN116449275A (en) | Receiving coil device for magnetic resonance imaging and magnetic resonance imaging system | |
| CN114631033A (en) | Magnetic resonance volume coil with multiple independent transmit receive channels | |
| CN113504494B (en) | Four-end ring birdcage radio frequency coil system supporting three-nuclide imaging |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |