Cable Arrangement for Use in a Magnetic Resonance Local Coil

Abstract

An antenna of a cable arrangement is provided for use in an MR local coil. An MR local coil with such a cable arrangement and a method for producing such a cable arrangement are provided. The cable arrangement includes an electrical conductor, which may have a material with a high electrical conductivity, such as copper for instance. The cable arrangement, in particular the electrical conductor, is embodied in a wavelike manner (e.g., the cable arrangement has a waveform).

Claims

1. A cable arrangement for use in a magnetic resonance (MR) local coil, the cable arrangement comprising: an electrical conductor, wherein the electrical conductor has a wavelike shape in the MR local coil.

2. The cable arrangement of claim 1, further comprising: an elastic carrier.

3. The cable arrangement of claim 2, wherein the electrical conductor is connected to the elastic carrier in a two-dimensional manner.

4. The cable arrangement of claim 2, wherein the elastic carrier is arranged on at least two opposing sides of the electrical conductor.

5. The cable arrangement of claim 2, wherein the electrical conductor is arranged on at least two opposing sides of the elastic carrier.

6. The cable arrangement of claim 2, wherein the electrical conductor is at least partially encased by the elastic carrier, the elastic carrier is at least partially encased by the electrical conductor, or a combination thereof.

7. The cable arrangement of claim 2, wherein the elastic carrier comprises plastic.

8. The cable arrangement of claim 1, wherein the electrical conductor is planar and wavelike shaped.

9. The cable arrangement of claim 1, further comprising: a neutral fiber and the electrical conductor is disposed in the neutral fiber.

10. The cable arrangement of claim 1, further comprising: a tissue of at least two longitudinal threads, a number of transverse threads, or the at least two longitudinal threads and the number of transverse threads.

11. The cable arrangement of claim 10, wherein the number of transverse threads is arranged alternately in wave troughs and wave crests in the wavelike conductor.

12. The cable arrangement of claim 1, wherein the cable arrangement further comprises a rigid housing, in which the electrical conductor is arranged, and wherein the rigid housing delimits an expansion of the electrical conductor.

13. The cable arrangement of claim 1, wherein cable arrangement is encased with a foamed material.

14. A magnetic resonance (MR) local coil comprising: an antenna with an electrical conductor that is wavelike.

15. The MR local coil of claim 14, further comprising: a protective sheath.

16. The MR local coil of claim 15, wherein the protective sheath comprises foam, compound, granulate, liquid, or a combination thereof.

17. A method for producing a cable arrangement for use in a magnetic resonance (MR) local coil, the method comprising: connecting an electrical conductor to an elastic carrier by a hot stamping process, by electroplating, or by both the hot stamping process and the electroplating; and positioning the connected electrical conductor and the elastic carrier in the MR local coil.

18. The method of claim 17, further comprising: injection molding the electrical conductor and the elastic carrier.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Further advantages, features and details are disclosed in the exemplary embodiments described below and with the aid of the drawings. Parts which correspond to one another are provided with the same reference characters in all the figures.

[0057] FIG. 1 shows an exemplary cable arrangement with an elastic conductor, which is surrounded by an elastic carrier, at least partially, in a schematic representation,

[0058] FIG. 2 shows a further exemplary cable arrangement with an electrical conductor, which is arranged in a neutral fiber, in a schematic representation,

[0059] FIG. 3 shows a further exemplary cable arrangement with an elastic carrier, which is surrounded by an electrical conductor, at least partially, in a schematic representation,

[0060] FIG. 4 shows a further exemplary cable arrangement with a tissue in a first expansion state in a schematic representation,

[0061] FIG. 5 shows a further exemplary cable arrangement with a tissue in a second expansion state in a schematic representation,

[0062] FIG. 6 shows a further exemplary cable arrangement with an encasing in a schematic representation,

[0063] FIG. 7 shows a further exemplary cable arrangement with an encasing in a schematic cross-sectional representation,

[0064] FIG. 8 shows an exemplary MR local coil with an optional protective sheath in a schematic representation,

[0065] FIG. 9 shows an exemplary method for producing a cable arrangement in a block diagram, and

[0066] FIG. 10 shows an exemplary magnetic resonance apparatus with an MR local coil in a schematic representation.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0067] FIG. 10 shows a schematic representation of a magnetic resonance apparatus 10. The magnetic resonance apparatus 10 includes a magnet unit 11 that has a main magnet 12 for generating a strong and in particular temporally constant main magnetic field 13. Moreover, the magnetic resonance apparatus 10 includes a patient receiving area 14 for receiving a patient 15. In the present exemplary embodiment, the patient receiving area 14 is embodied to be cylindrical and in a peripheral direction is surrounded by the magnet unit 11 in the manner of a cylinder. In principle, however, a configuration of the patient receiving area 14 deviating therefrom is readily conceivable. The patient 15 may be pushed into the patient receiving area 14 by a patient support apparatus 16 of the magnetic resonance apparatus 10. For this purpose, the patient support apparatus 16 has a patient couch 17 configured to be movable within the patient receiving area 14.

[0068] The magnet unit 11 also has a gradient coil unit 18 for generating magnetic field gradients that are used for position encoding during imaging. The gradient coil unit 18 is controlled by a gradient control unit 19 of the magnetic resonance apparatus 10. The magnet unit 11 further includes a high frequency antenna unit 20, which, in the present exemplary embodiment, includes a body coil and an MR local coil 26 that are fixedly integrated in the magnetic resonance apparatus 10 and arranged locally on the body of the patient 15, respectively. The high frequency antenna unit 20 is configured to excite atomic nuclei situated in the main magnetic field 13 generated by the main magnet 12. The high frequency antenna unit 20 is controlled by a high frequency antenna control unit 21 of the magnetic resonance apparatus 10 and radiates high frequency magnetic resonance sequences into an examination space substantially formed by a patient receiving area 14 of the magnetic resonance apparatus 10. The high frequency antenna unit 20, in particular the MR local coil 26, is also embodied to receive magnetic resonance signals.

[0069] The magnetic resonance apparatus 10 has a system control unit 22 for controlling the main magnet 12, for controlling the gradient control unit 19, and for controlling the high frequency antenna control unit 21. The system control unit 22 centrally controls the magnetic resonance apparatus 10, such as for example the performance of a predetermined imaging gradient echo sequence. Furthermore, the system control unit 22 includes an evaluation unit, not disclosed in detail, for evaluating medical image data acquired during the magnetic resonance examination. Furthermore, the magnetic resonance apparatus 10 includes a user interface 23 connected to the system control unit 22. Control information, such as, for example, imaging parameters and reconstructed magnetic resonance images, may be displayed on a display unit 24, for example on at least one monitor, of the user interface 23 for medical operating personnel. In addition, the user interface 23 has an input unit 25 by which information and/or parameters may be input by the medical operating personnel during a scanning procedure.

[0070] FIG. 8 shows a schematic representation of an MR local coil 26. In this example, the MR local coil 26 includes two cable arrangements 100 with, in each case, one electrical conductor forming a closed loop. The cable arrangements 100 may function in particular as antenna elements for receiving magnetic resonance signals.

[0071] To provide a safety distance from the patient 15, but also biocompatibility and cleanability, the cable arrangement 100 may be placed in a protective sheath 200. According to requirements, the sheath 200 may include an expandable material, for instance, such as foam, compound and/or granulate, and/or a liquid, etc. Embodiments of the MR local coil without a protective sheath are however also possible.

[0072] FIG. 1 shows an antenna cable arrangement 100 for use in an MR local coil 26. In such cases, the cable arrangement 100 includes, aside from an electrical conductor 110 of copper for instance, an elastic carrier 120, which has plastic, in particular polyimide (PI) and/or polyoxymethylene (POM), for instance.

[0073] The cable arrangement 100 is embodied to be wavelike (e.g., it has a waveform). The waveform of the cable arrangement 100 has a number of wave crests and wave troughs along a longitudinal direction L that repeat periodically, here at intervals of a periodic length P. The wave crests are disposed above a reference line R and the wave troughs there below. The waveform also has an amplitude A, namely a distance between a maximum length max of a wave crest in relation to a minimum length min of a wave trough.

[0074] If a cable arrangement 100 thus structured is expanded in parallel to the longitudinal direction L, the waveform flattens (e.g., the amplitude A becomes smaller). The elastic carrier provides for a resetting into the original waveform.

[0075] The reference line R parallel to the longitudinal direction L runs through a number of averaging points P.sub.1, P.sub.2, P.sub.3, wherein the number of averaging points P.sub.1, P.sub.2, P.sub.3 are each by a spatial averaging of a respective section S.sub.1, S.sub.2 of the electrical conductor. Here the sections S.sub.1, S.sub.2 include a period length P. An averaging point P.sub.1, P.sub.2, P.sub.3 may be described by a position vector such as for instance the averaging point P.sub.1, by the position vector {right arrow over (r.sub.1)}. One possible mathematical formulation for {right arrow over (r.sub.n)} is:

[00001]$\stackrel{.fwdarw.}{r_n}=\frac{1}{V_n}.Math.{\int }_{S_n}.Math.\stackrel{->}{r}.Math.\mathrm{dV}$

[0076] In such cases, V.sub.n is the volume and r is the position vectors of the electrical conductor 110 in section S.sub.n.

[0077] As in FIG. 1, the elastic carrier 120 in FIG. 2 is also arranged on two opposing sides of the electrical conductor 110. Furthermore, a neutral fiber N is shown in FIG. 2, in which the electrical conductor 110 is disposed. As a result, the mechanical load is received predominantly by the elastic carrier 120 when expanded.

[0078] In the example shown in FIG. 3, the electrical conductor 110 is arranged on two opposing sides of the elastic carrier 120.

[0079] Therefore FIGS. 1 to 3 in particular show exemplary cable arrangements 100, in which the electrical conductor 110 and/or the elastic carrier 120 are at least partially encased by the elastic carrier 120 and/or the electrical conductor 110 in each case. Furthermore, the electrical conductor 110 is connected in a two-dimensional manner with the elastic carrier 120.

[0080] FIGS. 4 and 5 show a development of the cable arrangement 100, which here includes a tissue 130 with two longitudinal threads 131 and a number of transverse threads 132. In such cases, the number of transverse threads 132 are arranged alternately in wave crests and wave troughs of the wavelike cable arrangement 100. The cable arrangement 100 is compressed in FIG. 4, whereas it is extended in FIG. 5. The tissue 130 may advantageously be expanded up to a maximum length for instance by using an aramid yarn that provides tensile strength as a longitudinal thread 131, so that the tissue 130 protects the electrical conductor 110 from an overload.

[0081] By way of example, FIGS. 4 and 5 show the electrical conductor 110 surrounded by the elastic carrier 120 (e.g., the electrical conductor 110 is internal). It is however also possible for the elastic carrier 120 to be surrounded by the electric carrier 110.

[0082] A further development of the cable arrangement 100 is shown in FIGS. 6 and 7. Here the cable arrangement 100 has an encasing 140 with a foamed material.

[0083] The perspective views in FIGS. 4 to 7 also show that the electrical conductor 110 may be embodied in a planar manner. As shown by way of example in FIG. 5, the wavelike surface of the electrical conductor 110 has two parallel two-dimensional areas 111 and 112.

[0084] The cross-sectional surface of the electrical conductor 110 has a first expansion direction x and a second expansion direction which is perpendicular thereto. The first expansion direction may be significantly larger than the second expansion direction in a planar embodiment of the electrical conductor 110.

[0085] FIG. 9 shows a method for producing a cable arrangement 100 for use in an MR local coil 26. In act 500, the electrical conductor 110 is connected to an elastic carrier 120 by a hot stamping process and/or an electrical conductor 110 is electroplated onto an elastic carrier 120.

[0086] For instance, a planar copper conductor with polyimide top layers is baked by the hot stamping process. Contrary to conventional manufacturing processes of planar flexible conductor boards, a three-dimensional hot stamping tool is advantageously used here. The stamping tool yields a desired waveform with the lamination process and after a cooling. The result behaves advantageously similarly to a spring (e.g., the result may be expanded and bent up to a certain degree and springs back into its original shape in a fully elastic manner).

[0087] When an electrical conductor 110 is electroplated onto an elastic carrier 120, this may not involve an already existing copper conductor, which is still only shaped, but instead may involve a carrier material, for instance plastic and/or another coatable, above all MR-suitable elastic material.

[0088] The carrier material is shaped depending on requirements (e.g., the thickness and/or the width and/or the wave amplitude is adjusted in order to generate the required reset force). The carrier 120 thus produced is either already conductive or is made to be conductive. Depending on requirements, copper or a similar material with a high electric conductivity is electroplated in the required thicknesses onto the elastic carrier.

[0089] In an optional act 510, the electrical conductor 110 and the elastic carrier 120, particularly with foam, is injection molded.

[0090] Finally, it is noted again that the method described above in detail and the pattern generation unit and magnetic resonance apparatus disclosed are merely exemplary embodiments that may be modified by a person skilled in the art in a wide variety of ways without departing from the scope of the disclosure. Further, the use of the indefinite article “a” or “an” does not preclude that the relevant features can also be present plurally. Similarly, the expression “unit” does not exclude the relevant components consisting of a plurality of cooperating subcomponents which can also be spatially distributed if required.

[0091] It is intended that the foregoing description be regarded as illustrative rather than limiting, and that it be understood that all equivalents and/or combinations of embodiments are intended to be included in this description.

[0092] It is to be understood that the elements and features recited in the appended claims may be combined in different ways to produce new claims that likewise fall within the scope of the present disclosure. Thus, whereas the dependent claims appended below depend from only a single independent or dependent claim, it is to be understood that these dependent claims can, alternatively, be made to depend in the alternative from any preceding or following claim, whether independent or dependent, and that such new combinations are to be understood as forming a part of the present specification.