Magnetic resonance local coil and manufacturing method thereof

Abstract

The present invention relates to a local magnetic resonance coil, a magnetic resonance system having the local magnetic resonance coil, and a method for manufacturing the local magnetic resonance coil. The local magnetic resonance coil includes a housing, an antenna structure, and a frame for accommodating the antenna structure. The housing is flexible and encloses an interior space. The frame is rigid, at least in regions, and is fixedly connected to the housing. The antenna structure is arranged in the interior space of the housing and is held in place by the frame.

Description

Technical Field

[0001] The present invention relates to a magnetic resonance local coil, a magnetic resonance system having a magnetic resonance local coil, and a method for producing a magnetic resonance local coil. Background Art

[0002] In medical technology, imaging using magnetic resonance (MR), also known as magnetic resonance tomography (MRI), is characterized by high soft-tissue contrast. In this case, an excitation pulse is injected into an examination subject, typically a patient, using a magnetic resonance device. This triggers magnetic resonance signals within the patient. These signals are received as measurement data by the magnetic resonance device and used to reconstruct a magnetic resonance image.

[0003] Magnetic resonance signals are typically received using so-called local coils (also known as surface coils). Such MR local coils (i.e., magnetic resonance local coils) typically include one or more MR antennas (i.e., magnetic resonance antennas) and are arranged in the direct vicinity of the patient during a magnetic resonance examination.

[0004] To ensure a good fit of the MR local coil on the patient, it should be as light and flexible as possible. To ensure high patient comfort, the MR local coil should preferably act like a light blanket or cushion and at the same time be liquid-proof and sterilization-resistant.

[0005] To connect a flexible MR local coil to a magnetic resonance system, it typically has coil connections, such as plugs, that are accessible from the outside and arranged on the flexible housing of the MR local coil. A reliable, tight connection between the flexible housing and the coil connections is desirable. At the same time, the MR local coil should be as easy to manufacture as possible. The technical problem addressed by the present invention can be seen as providing an MR local coil that is as sealed from the outside as possible and can also be manufactured with as little effort as possible. Summary of the Invention

[0006] This object is achieved according to the present invention by a magnetic resonance local coil, a magnetic resonance system having a magnetic resonance local coil, and a method for producing a magnetic resonance local coil. Advantageous embodiments are described in the description.

[0007] Accordingly, an MR local coil is proposed, comprising a housing (or casing), an antenna structure, and a frame for accommodating the antenna structure. The housing is flexible and encloses an interior space. The frame is rigid, at least in regions, and is fixedly connected to the housing. The antenna structure is arranged in the interior space of the housing and is held in position by the frame.

[0008] The outer cover is flexible, in particular bendable and / or geometrically adaptable in all spatial directions. Advantageously, no significant force is required for this purpose. The outer cover preferably has a thickness of less than 5 mm, in particular less than 2 mm.

[0009] The housing encloses an interior space. Other components of the MR local coil can be arranged in this interior space. In particular, the antenna structure can be at least partially arranged in this interior space. The antenna structure is preferably flexible, in particular bendable, and / or geometrically adaptable in all spatial directions. Advantageously, the entire MR local coil is at least partially (at least regionally) flexible.

[0010] The at least one MR antenna of the antenna structure can, for example, have a round, particularly elliptical or circular, or figure-eight shape. The at least one MR antenna can, for example, be applied to a substrate, particularly a printed circuit board. The at least one MR antenna can, for example, comprise a wire and / or a coaxial cable. Advantageously, a voltage and / or current can be induced in the MR antenna by the magnetic resonance signal.

[0011] The frame is designed to be rigid, in particular inflexible and / or inflexible, at least in certain areas. The frame can be interrupted at one or more locations, but can be rigid in the areas between the interruptions.

[0012] The frame is fixedly connected to the housing. For example, the frame is adhesively bonded and / or welded to the housing. The frame is advantageously connected to the housing in a sealed, particularly liquid-tight manner. Preferably, liquid cannot penetrate into the interior of the housing at the connection between the frame and the housing. The frame advantageously facilitates easy assembly of the antenna structure within the interior of the housing.

[0013] Another embodiment of the MR local coil provides that the frame has multiple fracture sites. During the manufacturing process of the MR local coil, it can be advantageous to initially have only the desired fracture sites, which are then fractured during manufacturing, so that the frame then has multiple fracture sites. For example, the desired fracture sites in the frame can be designed as grooves.

[0014] Another embodiment of the MR local coil provides that the frame is connected to the housing by an ultrasonic weld. An especially stable and / or leak-tight, in particular airtight and watertight, connection can be produced by the ultrasonic weld.

[0015] Ultrasonic welding can be used to connect thermoplastics in a form-fitting or material-bonding manner. To this end, frictional heat is usually generated in the plastics by mechanical vibrations, causing the plastics to soften, melt, and bond.

[0016] Ultrasonic welding is also advantageously easier to integrate into the electronics manufacturing environment than, for example, thermal bonding processes, which are subject to higher, full-surface heat input and can also damage the electronics. Ultrasonic welding, on the other hand, introduces heat to the materials being welded in a targeted manner.

[0017] Another embodiment of the MR local coil provides that the housing includes an outer layer of artificial leather and / or a fabric coated with polyurethane (PU). Such materials are advantageously particularly resistant and / or easy to clean and / or pleasant to the touch. Such materials also include layers, particularly on the inner side, such as cushioning and / or sliding layers.

[0018] For example, a padding layer made of cotton padding can give the MR local coil a soft and / or cushion-like feel, so that the patient can advantageously feel the local coil in a more comfortable manner.

[0019] For example, the sliding layer can impart to the MR local coil the property that layers located within the housing, such as the antenna structure, can be moved more easily relative to one another because they rub less against one another. This can, for example, reduce the restoring forces that occur when the MR local coil is deformed.

[0020] It is also conceivable that the outer cover includes a sliding pad that provides both good cushioning and good sliding properties. Such a sliding pad can, for example, comprise a mesh fabric. Like separate sliding and padding layers, the sliding pad can be welded directly to the outer layer, for example, by at least one ultrasonic weld.

[0021] Another embodiment of the MR local coil provides that the housing has an opening for inserting the MR antenna into the housing. In particular, the housing has only one opening for inserting the MR antenna into the housing. Since there is only one opening, the number of potentially leaky areas in the housing can be reduced.

[0022] Another embodiment of the MR local coil provides that the frame adjoins the opening. The frame can serve as an aid for introducing the antenna structure into the interior of the housing. The possible arrangement directly adjoining the opening makes it particularly easy to introduce the antenna structure into the interior of the housing.

[0023] Another embodiment of the MR local coil provides that the housing has a planar top side, wherein the housing has a planar bottom side opposite the top side, wherein the top side and the bottom side are connected via a plurality of end sides, wherein the opening is arranged at one of the plurality of end sides.

[0024] The interior of the housing is preferably located between the upper and lower sides of the housing. The multiple end faces preferably each constitute an edge of the MR local coil. Corners may be formed at two abutting edges. The opening preferably extends only over a portion of the end face or edge of the MR local coil. The extent of the opening is preferably less than half the length of the end face or edge of the MR local coil. Therefore, the opening is advantageously designed to be small, thereby reducing the risk of leaks in the MR local coil.

[0025] Another embodiment of the MR local coil provides that the multiple end faces have circumferentially consistent outer seams, in particular, ultrasonic welds. In particular, the outer seams can extend along the edges and corners of the MR local coil. Preferably, the outer seams are consistent over the entire area of ​​the corners and edges of the MR local coil, excluding the areas of the openings. This makes the MR local coil feel particularly comfortable and substantial.

[0026] Another embodiment of the MR local coil provides that the frame has a guide structure which interacts with a counter structure of the antenna structure in such a way that the antenna structure is held in position within the housing.

[0027] Furthermore, during the manufacture of the MR local coil, the guide structure can be used to guide the antenna structure into the interior of the housing in a defined manner. The guide structure can, for example, include a groove and / or a tongue, along which the antenna structure can preferably be guided into the interior of the housing during the manufacture of the MR local coil.

[0028] Another embodiment of the MR local coil provides that the antenna structure has a slot and / or tongue, by which the antenna structure is held in position within the interior of the housing. For example, the tongue of the guide structure may engage (or mesh) in the slot of the antenna structure. It is also conceivable that the tongue of the antenna structure engages in a slot in the guide structure.

[0029] Holding the antenna structure in position preferably includes preventing the antenna structure from moving in at least one direction parallel to the upper side and / or the underside of the housing.

[0030] Another embodiment of the MR local coil provides that the magnetic resonance local coil comprises a cover which is detachably fastened to the housing in the region of the frame.

[0031] The cover is preferably designed to protect, in particular to seal, the inner space of the housing.For example, the frame can be detachably fixed to the housing by means of bolts.

[0032] Another embodiment of the MR local coil provides that the frame is clamped by the cover, thereby advantageously achieving a particularly good sealing of the interior of the housing.

[0033] Furthermore, a magnetic resonance system is proposed, which has at least one magnetic resonance local coil as described above. The advantages of the proposed MR local coil essentially correspond to those of the magnetic resonance system. The features, advantages, or alternative embodiments mentioned in the description of the MR local coil can also be transferred to the magnetic resonance system.

[0034] Furthermore, a method for producing one of the aforementioned MR local coils is proposed, in which a frame is broken at a plurality of breaking points, and an antenna structure is introduced into the housing along these breaking points. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Further advantages, features and details of the invention are apparent from the exemplary embodiments described below and from the accompanying drawings. Corresponding components are provided with the same reference numerals in all the figures.

[0036] In the attached figure:

[0037] Figure 1 A magnetic resonance system with an MR local coil is shown;

[0038] Figure 2 A stereoscopic view of an MR local coil is shown;

[0039] Figure 3 shows a cross section obtained by cutting through the MR local coil;

[0040] Figure 4 An outer cover having a frame for housing an antenna structure is shown;

[0041] Figure 5 A frame for housing an antenna structure is shown;

[0042] Figure 6 A detailed view of the housing with the frame is shown;

[0043] Figure 7 A block diagram of a method for producing an MR local coil is shown. DETAILED DESCRIPTION

[0044] exist Figure 1, a magnetic resonance imaging system 10 is schematically shown. The magnetic resonance imaging system 10 comprises a magnet unit 11 having a main magnet 12 for generating a strong and, in particular, temporally constant main magnetic field 13. Furthermore, the magnetic resonance imaging system 10 comprises a patient accommodation area 14 for accommodating a patient 15. In the present embodiment, the patient accommodation area 14 is cylindrical and is cylindrically surrounded by the magnet unit 11 in the circumferential direction. However, in principle, designs of the patient accommodation area 14 differing from this are conceivable at any time. The patient 15 can be pushed into the patient accommodation area 14 by means of a patient support device 16 of the magnetic resonance imaging system 10. For this purpose, the patient support device 16 comprises a patient table 17 that is movable within the patient accommodation area 14.

[0045] The magnet unit 11 also includes a gradient coil unit 18 for generating magnetic field gradients used for position encoding during imaging. The gradient coil unit 18 is controlled by a gradient control unit 19 of the magnetic resonance system 10. The magnet unit 11 also includes a high-frequency antenna unit 20, which in the present embodiment is designed as a body coil fixedly integrated into the magnetic resonance system 10. The high-frequency antenna unit 20 is designed to excite atomic nuclei 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 system 10 and transmits high-frequency magnetic resonance sequences into the examination volume, which is essentially formed by the patient accommodation area 14 of the magnetic resonance system 10. The high-frequency antenna unit 20 is also designed to receive magnetic resonance signals.

[0046] The magnetic resonance system 10 has a system control unit 22 for controlling the main magnet 12, the gradient control unit 19 and the high-frequency antenna control unit 21. The system control unit 22 centrally controls the magnetic resonance system 10, such as for example executing predetermined imaging gradient echo sequences.

[0047] The magnetic resonance system 10 also includes a flexible MR local coil 100 disposed directly on the patient 15 . The MR local coil 100 includes at least one magnetic resonance antenna and is designed to receive magnetic resonance signals via the at least one magnetic resonance antenna. However, it is also conceivable that the MR local coil, like the high-frequency antenna unit 20 , is also designed to transmit high-frequency magnetic resonance sequences. The received magnetic resonance signals are transmitted to a high-frequency antenna control unit 21 .

[0048] The system control unit 22 also includes an analysis unit (not shown in detail) for analyzing magnetic resonance signals detected during the magnetic resonance examination. The magnetic resonance system 10 also includes a user interface 23 connected to the system control unit 22. Control information, such as imaging parameters, and reconstructed magnetic resonance images can be displayed on a display unit 24 of the user interface 23, such as at least one monitor, for a medical operator. The user interface 23 also includes an input unit 25, through which the medical operator can enter information and / or parameters during the measurement process.

[0049] Figure 2 An exemplary MR local coil 100 is shown with a housing 101 and a cover 102. The housing 101 comprises, for example, artificial leather and / or a PU-coated fabric or consists of artificial leather and / or a PU-coated fabric. The cross section AA shown here is Figure 3 Shown in.

[0050] The housing 101 has a planar top side 101a and an opposite planar bottom side 101b. The interior of the housing or the MR local coil is located between the top side and the bottom side. Figure 2 At the four end sides shown, the upper side 101 a is connected to the lower side 101 b .

[0051] The MR local coil further comprises a frame 103, which is fixedly connected to the upper side 101a of the housing 101 at a surface 111, and an antenna structure 104, which includes at least one MR antenna and is arranged in the interior of the housing. The connection at surface 111 can be established, for example, by ultrasonic welding, so that the frame 103 is connected to the housing 101 via an ultrasonic weld.

[0052] Frame 103 is designed to accommodate and hold antenna structure 104 in place. To this end, the frame includes a guide structure 107, and antenna structure 104 includes a corresponding mating structure 106. Guide structure 107, in this case in the form of a groove, and mating structure 106, in this case in the form of a tongue, interact in such a way that antenna structure 104 is held in place within the interior of housing 101. Thus, antenna structure 104 cannot, for example, slide sideways.

[0053] Frame 103 Figure 4 and Figure 5 During the manufacturing process, the frame initially also includes the rated breaking locations 108, but these rated breaking locations are broken during the manufacturing process, so the frame has multiple breaking locations. Therefore, the frame 103 is designed to be rigid regionally between the breaking locations.

[0054] Figure 5The frame 103 shown in FIG has two transverse webs. These transverse webs can advantageously reinforce the frame 103, thereby enabling better handling of the frame during the manufacture of the MR local coil 100, particularly when welding the frame 103 to the housing 101. The two transverse webs preferably have additional predetermined breaking points at their ends, i.e., at the transition to the rest of the frame. Breaking the frame 103 at these predetermined breaking points allows for easy removal of the transverse webs, thereby creating a particularly large opening for inserting the antenna structure 104.

[0055] like Figure 3 and Figure 4 As shown, the housing 101 has an opening 109 at one of the end faces 101 for introducing the antenna structure 104 into the interior of the housing 101. The frame 103 adjoins the opening 109. Outside of the opening 109, the end faces 110 have a circumferentially consistent outer seam. The outer seam can be, for example, an ultrasonic weld.

[0056] Figure 2 and Figure 3 The cover 102 shown is detachably fastened to the housing in the region of the frame 103 . In this case, the frame 103 is clamped by the cover 102 .

[0057] Figure 7 A flow chart of a method for producing an MR local coil is shown.

[0058] In S1, the housing 101, including in particular the various lining materials, is produced by ultrasonic welding. In this process, a completely closed outer seam is formed in the visible area of ​​the MR local coil, or an outer seam is interrupted only in the area of ​​the housing cover, see Figure 4 It is also conceivable to carry out step S1 later in the production process, for example after S2 .

[0059] In the area of ​​the cover to be installed later, the frame 103 is welded to the housing 101, including in particular the various lining materials and / or cushioning layers and / or sliding layers, by ultrasonic welding in S2, whereby the various materials are firmly connected to the frame. The frame 103 is designed so that it provides as much surface area as is required for the welding process and is at the same time as thin as possible.

[0060] After the frame 103 is securely welded to the housing 101, in S3, the frame 103 is broken into a plurality of individual parts at its predetermined breaking points while still in the welded state. In particular, any stabilizing transverse webs of the frame 103 can be removed. Thus, despite its partially rigid design, a flexible, defined opening toward the interior of the housing 101 is created. The more predetermined breaking points the frame 103 has, the more flexible the opening.

[0061] In S4, the prepared antenna structure 104 is passed through the opening along the break into the housing 101. The passed antenna structure 104 comprises mating parts 106 and 112, which are placed against the frame 103 that has been broken in a defined manner, see respectively Figure 3 or Figure 6 .

[0062] Next, in S5, the cover 102 is screwed on and the frame 103, which is broken in a controlled manner, is clamped in a defined manner. Thus, the frame 103 ensures that the housing 101 cannot slip out of the clamping device.

[0063] like Figure 3 As shown, by screwing on the cover 102 , the outer cover 101 is compressed in a defined manner in the edge region and thus additionally achieves a seal.

[0064] In summary, it can be seen that the proposed MR local coil 100 advantageously requires no additional openings for introducing the antenna structure 104 into the housing 101 which then has to be closed again in a further step, for example by ultrasonic welding or gluing.

[0065] A further advantage can be achieved by the fact that the end product has a uniform outer seam and, in particular, no transitions in the seam are necessary, in particular at the transition from the inner seam to the outer seam, and are therefore also not visible from the outside.

[0066] Furthermore, such a seam is advantageously more robust than a possibly separate outer seam, since the closing seam must perfectly meet the rest of the outer seam. A consistent outer seam gives the product a more premium look and eliminates the need for additional work steps.

[0067] Finally, it should be noted again that the MR local coil 100, magnetic resonance system 10, and method described in detail above are merely exemplary embodiments, and those skilled in the art may modify these embodiments in various ways without departing from the scope of the present invention. Furthermore, the use of the indefinite article "a" or "an" does not preclude the presence of a plurality of the relevant features. Similarly, the term "unit" does not preclude the relevant component from being composed of a plurality of cooperating, possibly spatially dispersed, subcomponents.

Claims

1. A magnetic resonance local coil, comprising - an outer shell, which is designed to be flexible and encloses the interior space, a frame for accommodating the antenna arrangement, which is rigid at least in regions and is fixedly connected to the housing, an antenna structure having at least one magnetic resonance antenna, which is arranged in the interior space of the housing and is held in place by the frame, It is characterized by: The frame has a plurality of breaking points caused by breaking of the predetermined breaking points.

2. The magnetic resonance local coil according to claim 1, in, The frame is connected to the outer cover by ultrasonic welding.

3. The magnetic resonance local coil according to claim 1 , in, The outer cover comprises artificial leather and / or fabric coated with PU.

4. The magnetic resonance local coil according to claim 1, in, The housing has an opening for introducing the magnetic resonance antenna into the interior space of the housing.

5. The magnetic resonance local coil according to claim 4, in, The frame is adjacent to the opening.

6. The magnetic resonance local coil according to claim 4 or 5, in, The outer cover has a planar upper side, wherein the outer cover has a planar lower side opposite to the upper side, wherein the upper side and the lower side are connected via a plurality of end sides, Therein, the opening is arranged on one of the plurality of end sides.

7. The magnetic resonance local coil according to claim 6, in, The end sides have a circumferentially identical outer seam.

8. The magnetic resonance local coil according to claim 7, in, The outer seam is an ultrasonic weld.

9. The magnetic resonance local coil according to claim 1, in, The frame has a guiding structure that cooperates with the mating structure of the antenna structure to hold the antenna structure in place within the interior space of the housing.

10. The magnetic resonance local coil according to claim 1, in, The antenna structure has a slot and / or tongue by which the antenna structure is held in place within the housing.

11. The magnetic resonance local coil according to claim 1, in, The magnetic resonance local coil comprises a cover which is detachably fastened to the housing in the region of the frame.

12. The magnetic resonance local coil according to claim 11, in, The frame is clamped by the cover. 13 . A magnetic resonance system comprising at least one magnetic resonance local coil according to claim 1 .

14. A method for manufacturing a magnetic resonance local coil, the magnetic resonance local coil comprising - an outer shell, which is designed to be flexible and encloses the interior space, a frame for accommodating the antenna arrangement, which is rigid at least in regions and is fixedly connected to the housing, an antenna structure having at least one magnetic resonance antenna, which is arranged in the interior space of the housing and is held in place by the frame, in, The frame is broken at a plurality of predetermined breaking points, so that the frame has a plurality of induced breaking points, wherein the antenna structure is introduced into the interior of the housing along the breaking points. 15 . The method according to claim 14 , for producing a magnetic resonance local coil according to claim 2 .

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