Ceramic ring surface cable wave trap

Abstract

The invention relates to a ceramic toroidal cable trap. A current cable trap includes a ceramic torus body having a first end and a second end. The ceramic torus body includes a groove disposed on a surface of the ceramic torus body and extending between the first end and the second end. The current cable trap also includes a conductive trace formed within the trench. A method for manufacturing a current cable trap includes forming a ceramic torus body having a first end and a second end. The ceramic torus body includes a groove disposed on a surface of the ceramic torus body and extending between the first end and the second end. A groove extends between the first end and the second end along both the inner surface and the outer surface of the ceramic torus body. The method also includes performing a metallization to form a conductive trace within the trench.

Description

Background Art

[0001] The subject matter disclosed herein relates to medical imaging and, more particularly, to ceramic toroidal cable traps.

[0002] Non-invasive imaging techniques allow images of internal structures or features of a patient / object to be obtained without performing an invasive procedure on the patient / object. Specifically, such non-invasive imaging techniques rely on various physical principles (such as differential transmission of X-rays through a target volume, reflection of acoustic waves within a volume, paramagnetism of different tissues and materials within a volume, decomposition of target radionuclides within the body, etc.) to acquire data and construct an image or otherwise represent the observed internal features of the patient / object.

[0003] During magnetic resonance imaging (MRI), when a substance such as human tissue is subjected to a uniform magnetic field (polarization field B0), the individual magnetic moments of the spins in the tissue attempt to align with the polarization field, but precess around it in a random order at their characteristic Larmor frequency. If the substance or tissue is subjected to a magnetic field (excitation field B1) that is in the xy plane and close to the Larmor frequency, the net alignment moment or "longitudinal magnetization" M z can be rotated or "tilted" into the xy plane to produce a net transverse magnetic moment M t After the excitation signal B1 is terminated, a signal is emitted by the excited spins and can be received and processed to form an image.

[0004] When these signals are used to generate images, the magnetic field gradient (G x , G y and G z ). Typically, the area to be imaged is scanned in a series of measurement cycles in which these gradient fields are varied according to the particular localization method used. The resulting set of received nuclear magnetic resonance (NMR) signals is digitized and processed to reconstruct an image using one of the well-known reconstruction techniques.

[0005] Typically, one or more baluns or floating cable traps are provided along the cable that connects a radio frequency (RF) coil (e.g., a body coil) to an MRI system. For patient safety, the floating cable trap reduces the current along the cable. Typically, these floating cable traps are prone to detuning and typically need to be placed far apart along the cable to avoid detuning. In addition, these floating cable traps are typically large and bulky. The large size and mass of the floating cable traps make it difficult to place the cable in the proper position for the patient. In addition, these floating cable traps generate a large amount of heat. These floating cable traps are highly position sensitive and must be placed at specific wavelength intervals to achieve optimal performance and minimize heating. Further usability studies have shown that the large size of the floating cable traps often results in them being used as carrying handles, which has resulted in the placement of the baluns being offset. Summary of the invention

[0006] The following shows an overview of certain embodiments disclosed herein. It should be understood that these aspects are provided only to provide the reader with a brief overview of these specific embodiments, and these aspects are not intended to limit the scope of the present disclosure. In fact, the present disclosure may cover various aspects that may not be shown below.

[0007] In one embodiment, a current cable trap is provided. The current cable trap includes a ceramic toroidal body having a first end and a second end. The ceramic toroidal body includes a groove disposed on a surface of the ceramic toroidal body and extending between the first end and the second end. The current cable trap also includes a conductive trace formed within the groove.

[0008] In another embodiment, a method for making a current cable trap is provided. The method includes forming a ceramic toroidal body having a first end and a second end. The ceramic toroidal body includes a groove disposed on a surface of the ceramic toroidal body and extending between the first end and the second end. The groove extends along both the inner surface and the outer surface of the ceramic toroidal body between the first end and the second end. The method also includes performing metallization to form a conductive trace within the groove.

[0009] In another embodiment, a cable for a radio frequency receiving coil assembly is provided, which is configured for use with a magnetic resonance imaging system. The cable includes a plurality of current cable traps arranged around the cable. Each of the plurality of current cable traps includes an additively manufactured ceramic toroidal body having a first end and a second end. The additively manufactured ceramic toroidal body includes a groove, which is disposed on a surface of the additively manufactured ceramic toroidal body and extends between the first end and the second end. Each of the plurality of current cable traps includes a conductive trace formed in the groove via metallization. Each of the plurality of current cable traps is configured to be insensitive to detuning caused by temperature changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] These and other features, aspects, and advantages of the present subject matter will be better understood when the following detailed description is read with reference to the accompanying drawings, in which like characters refer to like parts throughout the several views, and in which:

[0011] Figure 1 An embodiment of a magnetic resonance imaging (MRI) system suitable for use with the disclosed technology is illustrated;

[0012] Figure 2 is a schematic diagram of an RF receive coil array and its topology according to various aspects of the present disclosure;

[0013] Figure 3 is a schematic diagram of an RF receive coil array with an internal balun or current cable trap according to aspects of the present disclosure;

[0014] Figure 4 is a schematic diagram of a circuit formed between a cable and a balun or current cable trap according to aspects of the present disclosure;

[0015] Figure 5 A schematic diagram depicting a perspective view of a ceramic toroidal body (eg, having grooves arranged parallel to a longitudinal axis) of a current cable trap according to aspects of the present disclosure;

[0016] Figure 6 Describes various aspects of the present disclosure Figure 5 A schematic diagram of another perspective view of the ceramic toroidal body of the current cable trap in FIG.

[0017] Figure 7 Describes various aspects of the present disclosure Figure 5 A schematic diagram of an end view of a ceramic toroidal body of a current cable trap in FIG.

[0018] Figure 8 A schematic diagram depicting an end view of a ceramic toroidal body (eg, having two halves) of a current cable trap according to aspects of the present disclosure;

[0019] Fig. 9 A schematic diagram depicting a side view of a ceramic toroidal body (eg, having grooves arranged parallel to a longitudinal axis) of a current cable trap according to aspects of the present disclosure;

[0020] Fig.10 depicts a schematic diagram of a cross-section of a portion of a current cable trap having a ceramic toroidal body and conductive traces in accordance with aspects of the present disclosure;

[0021] Fig.11 depicts a schematic diagram of a cross section of a portion of a current cable trap having a ceramic toroidal body, conductive traces, and an insulating layer in accordance with aspects of the present disclosure;

[0022] Fig.12 A schematic diagram depicting a top view of a portion of a current cable trap having a conductor coupled to (eg, directly coupled to) a conductive trace in accordance with aspects of the present disclosure;

[0023] Fig.13 A schematic diagram depicting a top view of a portion of a current cable trap having a conductor coupled to a conductive trace (e.g., having a segmented conductive trace) according to aspects of the present disclosure;

[0024] Fig.14 A schematic diagram depicting a top view of a portion of a current cable trap having a conductor coupled to a conductive trace (e.g., with a recess adjacent a groove to accommodate the conductor) according to aspects of the present disclosure;

[0025] Fig.15 Schematic diagram depicting a top view of a portion of a current cable trap having a conductor coupled to a conductive trace (e.g., with a recess in the side of the groove to accommodate the conductor) according to aspects of the present disclosure;

[0026] Fig.16 depicts a schematic diagram of an RF receive coil assembly having a current cable trap disposed around a cable in accordance with aspects of the present disclosure;

[0027] Fig.17 A method for manufacturing a current cable trap according to aspects of the present disclosure is described.

[0028] Fig.18 depicts a schematic diagram of a cross-sectional view of a portion of a current cable trap having parallel grooves with corresponding conductors; and

[0029] Fig.19 A schematic diagram depicting a top view of a portion of a current cable trap having parallel grooves with corresponding conductors. DETAILED DESCRIPTION

[0030] One or more specific embodiments will be described below. In order to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be understood that in the development of any such actual implementation, as in any engineering or design project, many implementation-specific decisions must be made to achieve the developer's specific goals, such as complying with system-related and business-related constraints that may vary from implementation to implementation. In addition, it should be understood that such development efforts may be complex and time-consuming, but are still routine tasks for design, fabrication, and manufacturing for ordinary technicians who benefit from this disclosure.

[0031] When introducing elements of various embodiments of the present subject matter, the articles "a," "an," "the," and "said" are intended to indicate that there are one or more elements. The terms "comprising," "including," and "having" are intended to be inclusive, and mean that there may be additional elements in addition to the listed elements. Furthermore, any numerical examples in the following discussion are intended to be non-limiting, and thus the additional numerical values, ranges, and percentages are within the scope of the disclosed embodiments.

[0032] Although various aspects of the following discussion are provided in the context of medical imaging, it should be understood that the technology disclosed in the present invention is not limited to such medical contexts. In fact, the examples and explanations are provided in such medical contexts only to facilitate explanation by providing examples of realistic specific implementations and applications. However, the technology disclosed in the present invention can also be used in other contexts, such as non-destructive inspection of manufactured parts or goods (i.e., quality control or quality review application scenarios) and / or image reconstruction of non-invasive inspection of packages, boxes, suitcases, etc. (i.e., security inspection or screening application scenarios). In general, the technology disclosed in the present invention can be used in any imaging or screening context or image processing or photography field, in which a group or class of collected data undergoes a reconstruction process to generate an image or volume.

[0033] The present disclosure provides a current cable trap (e.g., a floating cable trap) or a balanced-unbalanced converter having a ceramic toroidal body. The current cable trap includes a ceramic toroidal body having a first end and a second end. The ceramic toroidal body includes a groove, which is disposed on the surface of the ceramic toroidal body and extends between the first end and the second end. The current cable trap also includes a conductive trace formed in the groove. In certain embodiments, the current cable trap is additively manufactured together with the groove (e.g., via three-dimensional (3D) printing). In certain embodiments, a conductive trace (e.g., a metal trace or a metal plate) is formed in the groove via a metallization process. In certain embodiments, the groove extends along both the inner surface and the outer surface of the ceramic toroidal body between the first end and the second end. In certain embodiments, the conductive trace is disposed below the outermost surface of the adjacent groove of the ceramic toroidal body. In certain embodiments, the current cable trap also includes an insulating layer, which is disposed in each groove in the groove between the corresponding conductive trace and the surface of the ceramic toroidal body.

[0034] In certain embodiments, the current cable trap includes one or more capacitors disposed on the ceramic toroidal body and configured to tune the current cable trap to a desired frequency. In certain embodiments, at least one of the conductive traces is segmented into at least two segments. In certain embodiments, at least one of the one or more capacitors is disposed between and coupled to at least two segments within one of the grooves. In certain embodiments, the one or more capacitors may be coupled in series with one of the grooves. In certain embodiments, the ceramic toroidal body includes at least one recessed portion formed adjacent to at least one of the grooves. In certain embodiments, at least one of the one or more capacitors is disposed within at least one recessed portion and coupled to one of the conductive traces.

[0035] In certain embodiments, the ceramic toroidal body is formed as a single piece.In certain embodiments, the ceramic toroidal body is formed as two halves that are configured to be coupled together around a cable to form a ceramic toroidal body that is configured to surround a cable.

[0036] In some embodiments, the groove is arranged parallel to a longitudinal axis extending between the first end and the second end of the ceramic toroidal body. In some embodiments, the groove is arranged in a non-parallel arrangement relative to the longitudinal axis. In some embodiments, the groove is arranged at an angle greater than zero degrees relative to the longitudinal axis extending between the first end and the second end of the ceramic toroidal body. In some embodiments, the current cable trap is configured to be insensitive to detuning caused by temperature changes.

[0037] In certain embodiments, a method for manufacturing a current cable trap is provided, the method comprising forming a ceramic toroidal body having a first end and a second end. The ceramic toroidal body comprises a groove disposed on a surface of the ceramic toroidal body and extending between the first end and the second end. The groove extends along both the inner surface and the outer surface of the ceramic toroidal body between the first end and the second end. The method further comprises performing metallization to form a conductive trace within the groove. In certain embodiments, forming the ceramic toroidal body comprises additively manufacturing (e.g., 3D printing) the ceramic toroidal body. In certain embodiments, an insulating layer is disposed within each groove in the groove between the corresponding conductive trace and the surface of the ceramic toroidal body. In certain embodiments, the method comprises forming the ceramic toroidal body as a single part. In certain embodiments, the method comprises forming the ceramic toroidal body into two halves, the two halves being configured to be coupled together around a cable to form a ceramic toroidal body configured to surround the cable.

[0038] In certain embodiments, a cable for a radio frequency receiving coil assembly includes a plurality of current cable traps disposed around the cable, the radio frequency receiving coil assembly being configured for use with a magnetic resonance imaging system. Each of the plurality of current cable traps includes an additively manufactured ceramic toroidal body having a first end and a second end. The additively manufactured ceramic toroidal body includes a groove disposed on a surface of the additively manufactured ceramic toroidal body and extending between the first end and the second end. Each of the plurality of current cable traps includes a conductive trace formed in the groove via metallization. Each of the plurality of current cable traps is configured to be insensitive to detuning caused by temperature changes. In addition, in certain embodiments (when the ceramic toroidal body has two halves) each current cable trap is configured to be removed from the cable (e.g., when damaged) without the need to remove other current cable traps disposed along the cable. In some embodiments, a cable couples a radio frequency (RF) receive coil assembly to a connector configured to couple the RF receive coil assembly to an MRI system (e.g., having a current cable trap located external to the RF receive coil assembly). In some embodiments, the cable (e.g., having a current cable trap) is disposed within a housing of a radio frequency receive coil assembly having an RF coil configured for use with an MRI system.

[0039] Although the current cable trap is discussed in the context of an MRI system, the current cable trap can be used in a dual imaging modality system. For example, the current cable trap can be used with a positron emission tomography (PET) / MRI system.

[0040] The shape of the ceramic toroidal cable trap disclosed herein (made as described herein) is very consistent and is not significantly affected by temperature or stress (e.g., caused by bending of the cable to which the current cable trap is coupled). Ceramic toroidal current traps are simpler to manufacture and do not require conductors to be wrapped around a body or structure to create inductance. The construction of ceramic toroidal cable traps is consistent and their shape is smaller than typical current cable traps, reducing the possibility of local heating. The combined performance of multiple ceramic toroidal cable traps suppresses common mode currents generated along system cables and internal coil cable wiring. In addition to reducing the risk of patient burns, overall coil heating is also reduced, making the coil safer without requiring as much insulation material. This makes the cable safer and lighter. In certain embodiments, because a single current cable trap has a split construction (when the ceramic toroidal body has two halves), it can be removed and replaced individually along the cable, so the current cable trap disclosed herein also improves maintainability. The disclosed current cable traps allow for reduced work time in assembling current cables (eg, faster cable assembly time because tuning or finishing is minimized) and reduced material costs (eg, because no internal material is required within the coil).

[0041] Considering the above, Figure 1 , a magnetic resonance imaging (MRI) system 100 is schematically illustrated as including a scanner 102, scanner control circuitry 104, and system control circuitry 106. According to embodiments described herein, the MRI system 100 is generally configured to perform MR imaging.

[0042] The system 100 also includes a remote access and storage system or device, such as a picture archiving and communication system (PACS) 108, or other devices, such as teleradiology equipment, that enable on-site or off-site access to data acquired by the system 100. In this way, MR data can be acquired and then processed and evaluated on-site or off-site. Although the MRI system 100 can include any suitable scanner or detector, in the illustrated embodiment, the system 100 includes a whole body scanner 102 having a housing 120 through which an aperture 122 is formed. An examination table 124 can be moved into the aperture 122 to allow a patient 126 (e.g., a subject) to be positioned therein to image selected anatomical structures within the patient's body.

[0043] The scanner 102 includes a series of associated coils for generating a controlled magnetic field for exciting gyromagnetic materials within the anatomical structure of the patient being imaged. Specifically, a primary magnetic coil 128 is provided for generating a primary magnetic field B0 that is generally aligned with the orifice 122. A series of gradient coils 130, 132, and 134 allow controlled gradient magnetic fields to be generated during an examination sequence for position encoding of certain gyromagnetic nuclei within the patient 126. A radio frequency (RF) coil 136 (e.g., an RF transmit coil) is configured to generate radio frequency pulses for exciting certain gyromagnetic nuclei within the patient. In addition to the coils that may be located locally at the scanner 102, the system 100 also includes a set of receiving coils or RF receiving coils 138 (e.g., a coil array) configured to be placed proximal to the patient 126 (e.g., against the patient). For example, the receiving coil 138 may include a cervical / thoracic / lumbar (CTL) coil, a head coil, a single-sided spine coil, etc. Generally, the receive coil 138 is placed near or on top of the patient 126 to receive the weak RF signals (weak relative to the transmit pulses generated by the scanner coil) generated by certain gyromagnetic nuclei in the patient's body when the patient 126 returns to his or her relaxed state.

[0044] As described in more detail below, one or more current cable traps may be arranged to surround a cable of an RF receive coil. The current cable trap may include a ceramic toroidal body. In certain embodiments, the ceramic toroidal body may be a single part. In certain embodiments, the ceramic toroidal body may be two halves coupled (e.g., snapped) together around a cable of the RF receive coil. The current cable trap includes a groove that is arranged (e.g., formed) in a surface of the ceramic toroidal body. Conductive traces or conductive plates are formed in the corresponding ceramic toroidal body of the current cable trap. This does not require winding a conductor wire around the structure to create an inductance. The current cable trap with a ceramic toroidal body is not significantly affected by temperature or stress (e.g., caused by bending of the cable to which the current cable trap is attached).

[0045] The various coils of the system 100 are controlled by external circuitry to generate the required fields and pulses and to read the emission from the gyromagnetic material in a controlled manner. In the illustrated embodiment, the main power supply 140 provides power to the primary field coil 128 to generate the primary magnetic field Bo. The power input (e.g., power from a utility or grid), a power distribution unit (PDU), a power supply (PS), and a drive circuit 150 can provide power together to pulse the gradient field coils 130, 132, and 134. The drive circuit 150 may include an amplification and control circuit system for supplying current to the coils as defined by the digitized pulse sequence output by the scanner control circuit system 104.

[0046] Another control circuit 152 is provided for regulating the operation of the RF coil 136. The circuit 152 includes a switching device for alternating between an active mode of operation and a passive mode of operation, wherein the RF coil 136 transmits and does not transmit a signal, respectively. The circuit 152 also includes an amplification circuit system configured to generate RF pulses. Similarly, the receiving coil 138 is connected to a switch 154 that is capable of switching the receiving coil 138 between a receiving mode and a non-receiving mode. Thus, in the receiving mode, the receiving coil 138 resonates with the RF signal generated by the release of the gyromagnetic nuclei in the patient 126, and in the non-receiving mode, they do not resonate with the RF energy from the transmitting coil (i.e., the coil 136) to prevent undesired operation. In addition, the receiving circuit 156 is configured to receive data detected by the receiving coil 138, and may include one or more multiplexing and / or amplification circuits.

[0047] It should be noted that although the scanner 102 and control / amplification circuit system described above are illustrated as being coupled by a single line, in actual examples there may be many such lines. For example, separate lines may be used for control, data communication, power transmission, etc. In addition, appropriate hardware may be provided along each type of line for properly processing data and current / voltage. In practice, various filters, digitizers, and processors may be provided between the scanner and either or both of the scanner control circuit 104 and the system control circuit system 106.

[0048] As shown, the scanner control circuit system 104 includes an interface circuit 158 ​​that outputs signals for driving the gradient field coils and the RF coils and for receiving data representing magnetic resonance signals generated in the examination sequence. The interface circuit 158 ​​is coupled to a control and analysis circuit 160. Based on a defined scheme selected via the system control circuit 106, the control and analysis circuit 160 executes commands for driving the circuits 150 and 152.

[0049] The control and analysis circuitry 160 is also used to receive magnetic resonance signals and perform subsequent processing before transmitting the data to the system control circuitry 106. The scanner control circuitry 104 also includes one or more memory circuits 162 that store configuration parameters, pulse sequence descriptions, examination results, etc. during operation.

[0050] Interface circuit 164 is coupled to control and analysis circuit 160 for exchanging data between scanner control circuit system 104 and system control circuit system 106. In some embodiments, control and analysis circuit 160, although shown as a single unit, may include one or more hardware devices. System control circuit 106 includes interface circuit 166, which receives data from scanner control circuit system 104 and transmits data and commands back to scanner control circuit system 104. Control and analysis circuit 168 may include a CPU in a general or special computer or workstation. Control and analysis circuit 168 is coupled to memory circuit 170 to store programming code for operating MRI system 100, and to store processed image data for later reconstruction, display and transmission. The programming code may execute one or more algorithms that are configured to perform reconstruction of acquisition data as described below when executed by a processor. In some embodiments, image reconstruction may occur on a separate computing device having a processing circuit system and a memory circuit system.

[0051] Additional interface circuitry 172 may be provided for exchanging image data, configuration parameters, etc. with external system components (such as remote access and storage device 108). Finally, system control and analysis circuitry 168 may be communicatively coupled to various peripheral devices for facilitating operator interface and generating hard copies of reconstructed images. In the illustrated embodiment, these peripheral devices include a printer 174, a monitor 176, and a user interface 178, which includes devices such as a keyboard, a mouse, a touch screen (e.g., integral to the monitor 176), and the like.

[0052] Figure 2 FIG. 1 is a schematic diagram of an RF receive coil array or assembly 180 and its topology. The shape and size of the RF receive coil array 180 may be different from the Figure 2 RF receive coil array 180 may be used in an MRI system (e.g., Figure 1 The MRI system 100 in FIG. 1 includes an RF receive coil array 180 that includes an RF coil 182 (eg, a flexible RF coil) having a plurality of loops 184 (eg, elements or channels).

[0053] like Figure 2As depicted, the plurality of rings 184 includes eight rings (although the number of rings 184 may vary). Each ring 184 is coupled to an electronics unit 185, which is coupled to a coil interface cable 186. The coil interface cable 186 of each of the rings 184 is coupled to a balun 187 (e.g., an integrated balun cable harness). Each electronics unit 185 may include various components (e.g., a decoupling circuit, an impedance inverter circuit, and a preamplifier). The balun 187 may act as an RF trap. The balun 187 is coupled (via cable 188) to a P connector 190 (e.g., a port connector) that enables the RF receive coil 180 to be coupled to an interface of the MRI system that couples the imaging component to the processing component.

[0054] Ring 184 is disposed within housing 191. In certain embodiments, the housing may be flexible. Figure 2 As depicted, each loop 184 partially overlaps at least one adjacent loop 184. In certain embodiments, one or more RF coils 182 may be designed using AIR™ coil technology from General Electric Healthcare. This enables the RF coils 182 to be lightweight and flexible.

[0055] As shown, a plurality of baluns or current cable traps 192 (e.g., RF traps) having a ceramic toroidal body made from a single part or two halves are disposed around the cable 188, as described in more detail below. In certain embodiments, one or more of these baluns or current cable traps 192 may be disposed internally (e.g., within the housing 191), for example, around one of the cables 186, such as Figure 3 Schematically shown in FIG.

[0056] Figure 4 is formed on the cable 196 (e.g., Figure 2 186 or cable 188 in FIG. 18 and a plurality of baluns or current cable traps 192. The baluns or current cable traps 192, each having a ceramic toroidal body, are made from a single part or two halves, as described in more detail below. As shown, four current cable traps 192 are arranged around the cable 196. The number of current cable traps 192 may vary. Mutual inductance (M) 198 is formed between each current cable trap 192 and the cable 196. The current cable traps 192 insert a large amount of impedance, substantially blocking the path of current at the proton frequency. Specifically, the current cable traps 192 suppress common mode currents that may cause RF burns to the patient.

[0057] Figures 5 to 7 Depicts a current cable trap (e.g. Figure 2 and Figure 3 Schematic diagram of different views of a ceramic toroidal body 200 of a current cable trap 192 in FIG. As shown, the ceramic toroidal body 200 is made or formed from a single part. In some embodiments, the ceramic toroidal body 200 is made from two halves (see FIG. Figure 8 ). The size of the ceramic toroidal body 200 is smaller than the typical size of the body or structure of the current cable wave trap. The ceramic toroidal body 200 is made of a ceramic material that does not deform with temperature changes. Therefore, the ceramic toroidal body 200 (and the current cable wave trap) is configured to be insensitive to detuning caused by temperature changes. The ceramic toroidal body 200 has a first end 202 (e.g., a first longitudinal end) and a second end 204 (e.g., a second longitudinal end 204). The ceramic toroidal body 200 includes a plurality of grooves 206 (e.g., channels) disposed on (e.g., formed on) a surface 208 of the ceramic toroidal body 200. The surface 208 of the ceramic toroidal body 200 extends from an inner portion 210 of the ceramic toroidal body 200 that is disposed around the orifice 212 to an outer portion 214 of the ceramic toroidal body 200 (e.g., facing away from the orifice 212). Thus, the surface 208 on the inner portion 210 is an inner surface, while the surface 208 on the outer portion 214 is an outer surface.

[0058] As shown, the grooves 206 extend along the surface 208 (of the inner portion 210 and the outer portion 214) between the first end 202 and the second end 204. Specifically, the grooves 206 (e.g., the inner grooves 206 and the outer grooves 206) extend along (e.g., wrap around) the first end 202, the second end 204, the inner portion 210, and the outer portion 214 of the ceramic toroidal body 200. The depth and width of the grooves 206 may vary, depending on the application of the current cable trap. The number of grooves 206 on the ceramic toroidal body 200 may vary. As shown, the grooves 206 are arranged non-parallel with respect to the longitudinal axis 215 of the ceramic toroidal body 200. As shown, the grooves 206 are arranged at an angle 216 greater than zero degrees with respect to the longitudinal axis 215 between the first end 202 and the second end 204. On the ends 202, 204, the grooves 206 are disposed at an angle 218 greater than zero degrees relative to a line 220 perpendicular to the longitudinal axis 215. In certain embodiments, the grooves 206 are parallel to the longitudinal axis 215 between the ends 202, 204 and parallel to the line 220 on the ends 202, 204.

[0059] Conductive traces may be formed within the grooves 206 (e.g., via a metallization process such as a mask) to create an inductance when utilizing the current cable trap. This avoids having to wrap a wire conductor around the ceramic toroidal body 200 to create the inductance. The thickness of the conductive traces (in a direction toward the center of the orifice 212) may be adjusted to achieve the desired capacitance. In certain embodiments, the conductive traces are disposed below the outermost surface (on the inner portion 210 or the outer portion 214) of the ceramic toroidal body adjacent to the grooves 206, thereby preventing the conductive traces from being affected by the bending of the cable on which the current cable trap is disposed. In certain embodiments, one or more capacitors may be disposed on the ceramic toroidal body 200 and coupled to at least one conductive trace to tune the current cable trap to a desired frequency. In certain embodiments, one or more materials used as an insulating layer may be disposed between each conductive trace and the corresponding groove 206 to form a barrier between the ceramic toroidal body 200 and the conductive traces.

[0060] Figure 8 A schematic diagram of an end view of another ceramic toroidal body 222 (e.g., having two halves) of a current cable trap is depicted. As shown, the ceramic toroidal body 222 has a split toroidal configuration. Specifically, the ceramic toroidal body 222 is made or formed of two halves (e.g., a first body half 224 and a second body half 226). In certain embodiments, the first body half 224 and the second body half 226 can be coupled together by snapping them together around a cable. A single current cable trap that can be individually removed and replaced along a cable as needed is achieved using a split toroidal configuration.

[0061] The dimensions of the ceramic toroidal body 222 are smaller than typical dimensions of a body or structure of a current cable trap. Both halves 224, 226 of the ceramic toroidal body 222 are made of a ceramic material that does not deform with changes in temperature. Thus, the ceramic toroidal body 222 (and the current cable trap) are configured to be insensitive to detuning due to changes in temperature. Each half 224, 226 of the ceramic toroidal body 222 has a respective first end 202 (e.g., a first longitudinal end) and a respective second end 204 (e.g., a second longitudinal end 204). Each half 224, 226 of the ceramic toroidal body 222 includes a respective plurality of grooves 206 (e.g., channels) disposed on (e.g., formed on) a respective surface 208. The surface 208 of each half 224, 226 of the ceramic toroidal body 222 extends from an inner portion 210 of the half 224, 226 that is disposed about the aperture (when the halves 224, 226 are coupled) to an outer portion 214 of the half 224, 226 (e.g., facing away from the aperture). Thus, the surface 208 on the inner portion 210 is an inner surface, while the surface 208 on the outer portion 214 is an outer surface.

[0062] As shown, the grooves 206 on each respective half 224, 226 extend along the surface 208 (of the inner portion 210 and the outer portion 214) between the first end 202 and the second end 204. Specifically, the grooves 206 (e.g., the inner grooves 206 and the outer grooves 206) on each respective half 224, 226 extend along (e.g., wrap around) the first end 202, the second end 204, the inner portion 210, and the outer portion 214 of the ceramic toroidal body 222. The depth and width of the grooves 206 may vary, depending on the application of the current cable trap. The number of grooves 206 on the ceramic toroidal body 222 may vary. As shown, the grooves 206 on each half 224, 226 are arranged non-parallel with respect to the longitudinal axis 215 of the ceramic toroidal body 222. As shown, the grooves 206 are arranged at an angle 216 greater than zero degrees relative to the longitudinal axis 215 between the first end 202 and the second end 204 (similar to Figure 5 and Figure 6 ). On the ends 202 , 204 , the grooves 206 are disposed at an angle 218 greater than zero degrees relative to a line 220 perpendicular to the longitudinal axis 215 .

[0063] Conductive traces may be formed (e.g., via a metallization process such as a mask) within the grooves 206 of each half 224, 226 to create an inductance when utilizing the current cable trap. This avoids having to wrap a wire conductor around the ceramic toroidal body 200 to create the inductance. The thickness of the conductive traces (in a direction toward the center of the aperture) may be adjusted to achieve the desired capacitance. In certain embodiments, the conductive traces are disposed below the outermost surface (on the inner portion 210 or the outer portion 214) of the ceramic toroidal body 222 adjacent to the grooves 206, thereby preventing the conductive traces from being affected by the bending of the cable on which the current cable trap is disposed. In certain embodiments, one or more capacitors may be disposed on the ceramic toroidal body 222 and coupled to at least one conductive trace to tune the current cable trap to a desired frequency. In certain embodiments, one or more materials that function as an insulating layer may be disposed between each conductive trace and the corresponding groove 206 on each half 224, 226 to form a barrier between the ceramic toroidal body 222 and the conductive traces.

[0064] Fig. 9 A schematic diagram depicting a side view of another ceramic toroidal body 228 of a current cable trap (e.g., having grooves arranged parallel to the longitudinal axis). As shown, the ceramic toroidal body 228 is made or formed from a single piece. In some embodiments, the ceramic toroidal body 228 is made from two halves (see Figure 8 ). The dimensions of the ceramic toroidal body 228 are smaller than typical dimensions of a body or structure of a current cable trap. The ceramic toroidal body 228 is made of a ceramic material that does not deform with changes in temperature. Therefore, the ceramic toroidal body 228 (and the current cable trap) are configured to be insensitive to detuning caused by temperature changes. The ceramic toroidal body 228 has a first end 202 (e.g., a first longitudinal end) and a second end 204 (e.g., a second longitudinal end 204). The ceramic toroidal body 228 includes a plurality of grooves 206 (e.g., channels) disposed on (e.g., formed on) a surface 208 of the ceramic toroidal body 200. The surface 208 of the ceramic toroidal body 200 is configured from a portion of the ceramic toroidal body 228 that is disposed around the orifice 212 (e.g., similar to Figures 5 to 8 The inner portion of the ceramic toroidal body 228 extends to the outer portion 214 (eg, away from the orifice 212). Thus, the surface 208 on the inner portion is an inner surface, while the surface 208 on the outer portion 214 is an outer surface.

[0065] As shown, the grooves 206 extend along the surface 208 (of the inner portion and the outer portion 214) between the first end 202 and the second end 204. Specifically, the grooves 206 (e.g., the inner grooves 206 and the outer grooves 206) extend along (e.g., wrap around) the first end 202, the second end 204, the inner portion and the outer portion 214 of the ceramic toroidal body 228. The depth and width of the grooves 206 may vary, depending on the application of the current cable trap. The number of grooves 206 on the ceramic toroidal body 228 may vary. As shown, the grooves 206 are arranged non-parallel with respect to the longitudinal axis 215 of the ceramic toroidal body 228. As shown, the grooves 206 are parallel to the longitudinal axis 215 between the ends 202, 204. The grooves 206 are also parallel to the line 220 (see Figure 5 and Figure 6 )parallel.

[0066] Conductive traces may be formed within the grooves 206 (e.g., via a metallization process such as a mask) to create an inductance when utilizing the current cable trap. This avoids having to wrap a wire conductor around the ceramic toroidal body 228 to create the inductance. The thickness of the conductive traces (in a direction toward the center of the orifice 212) may be adjusted to achieve the desired capacitance. In certain embodiments, the conductive traces are disposed below the outermost surface (on the inner portion 210 or the outer portion 214) of the ceramic toroidal body adjacent to the grooves 206, thereby preventing the conductive traces from being affected by the bending of the cable on which the current cable trap is disposed. In certain embodiments, one or more capacitors may be disposed on the ceramic toroidal body 228 and coupled to at least one conductive trace to tune the current cable trap to a desired frequency. In certain embodiments, one or more materials used as an insulating layer may be disposed between each conductive trace and the corresponding groove 206 to form a barrier between the ceramic toroidal body 228 and the conductive traces.

[0067] Fig.10 A schematic diagram of a cross-section (e.g., taken along the middle of a groove 206) of a portion of a current cable trap 192 having a ceramic toroidal body 200 and a conductive trace 230 is depicted. As shown, the conductive trace 230 (e.g., a metal trace) is disposed on (e.g., formed on) a bottom surface 232 of the groove 206. The groove 206 may be located Figures 5 to 7204, the conductive trace 230 may be formed on an inner portion 210, an outer portion 214, a first end 202, or a second end 204 of a ceramic toroidal body 200 in the embodiment of the present invention. In certain embodiments, a conductive trace may be formed (e.g., via a metallization process such as a mask) within the groove 206 to create an inductance when the current cable trap 192 is utilized. This avoids having to wrap a wire conductor around the ceramic toroidal body 200 to create an inductance. The thickness 234 of the conductive trace 230 may be adjusted to achieve a desired capacitance. In certain embodiments, the conductive trace 230 is made of copper. In certain embodiments, the conductive trace 230 may be made of another type of metal (e.g., nickel) in non-MRI applications. As shown, the conductive trace 230 is disposed below an outermost surface 235 (on the inner portion 210 or the outer portion 214) of the ceramic toroidal body 200 adjacent to the groove 206, thereby preventing the conductive trace from being affected by bending of the cable on which the current cable trap 192 is disposed.

[0068] Fig.11 A schematic diagram of a cross-section of a portion of a current cable trap 192 having a ceramic toroidal body 200, a conductive trace 230, and an insulating layer 236 is depicted. The cable trap 192 is shown in FIG. Fig.10 206 , wherein the insulating layer 236 is not shown. As shown, the insulating layer 236 is disposed between the conductive trace 230 and the bottom surface 232 of the groove 206. The insulating layer 236 forms a barrier between the ceramic toroidal body 200 and the conductive trace 230. In some embodiments, more than one insulating layer 236 may be disposed between the ceramic toroidal body 200 and the bottom surface 232 of the groove 206. In this case, the multiple insulating layers may be made of different materials or the same material. In some embodiments, the insulating layer 236 may be an epoxy resin (e.g., ), glazes, masks, enamel coatings, ceramic coatings, glass frits or mechanical parts.

[0069] In certain embodiments, one or more capacitors may be disposed on the ceramic toroidal body 200 and coupled to at least the conductive trace 230 to tune the current cable trap 192 to a desired frequency. Fig.12 A schematic diagram depicting a top view of a portion of a current cable trap 192 having a conductor 238 coupled to (eg, directly coupled to) a conductive trace 230 is depicted. Fig.12 As depicted, a pair of conductors 238 are coupled (eg, soldered) directly in series to the conductive trace 230. The number of conductors 238 coupled to the conductive trace 230 may vary.

[0070] Fig.13A schematic diagram of a top view of a portion of a current cable trap 192 having a conductor 238 coupled to a conductive trace 230 (e.g., having a segmented conductive trace) is depicted. As shown, the conductive trace 230 is formed by segments 240 within the groove 206. A printed circuit board 242 is disposed between the segments 240 within the groove 206. The printed circuit board 242 includes a pair of conductors 238 that are coupled to the segments 240 of the conductive trace 230 via electrical connectors (not shown) on the printed circuit board 242. The number of conductors 238 can vary.

[0071] Fig.14 A schematic diagram of a top view of a portion of a current cable trap 198 having a conductor 238 coupled to a conductive trace 230 (e.g., with a recess adjacent to the groove 206 to accommodate the conductor 238) is depicted. During formation of the ceramic toroidal body 200, at least one recess 244 may be formed in the ceramic toroidal body 200 adjacent to at least one groove 206. A printed circuit board 242 is disposed within the recess 244. The printed circuit board 242 includes a pair of conductors 238 coupled to the conductive trace 230 via electrical connectors (not shown) on the printed circuit board 242. The number of conductors 238 may vary.

[0072] Fig.15 A schematic diagram of a top view of a portion of a current cable trap 192 having a conductor 238 coupled to a conductive trace 230 (e.g., with a recess in a side surface of a groove 206 to accommodate the conductor 238) is depicted. During formation of the ceramic toroidal body 200, at least one recess 244 may be formed in a side surface 246 of at least one groove 206. A printed circuit board 242 is disposed within the recess 244. The printed circuit board 242 includes a pair of conductors 238 coupled to the conductive trace 230 via electrical connectors (not shown) on the printed circuit board 242. The number of conductors 238 may vary.

[0073] Fig.16 A schematic diagram of an RF receive coil assembly 180 having a current cable trap 192 disposed around a cable 188 is depicted. Fig.11 As depicted, the current cable traps 192 can be closely packed together on the cable 188. The number of current cable traps 192 disposed on the cable 188 can vary. Due to their smaller size, the density of the current cable traps 192 on the cable 188 and at the coil interface is higher to enhance performance. In addition, the use of the current cable traps (as opposed to a standard balun) reduces the overall weight of the cable.

[0074] Other benefits of the toroidal shaped ceramic current cable traps are greater thermodynamic stability. Specifically, a cable with multiple toroidal shaped ceramic current cable traps takes less time to stabilize temperature than a cable with a standard cable balun. Multiple toroidal current cable traps distribute heat along the cable while eliminating cable hot spots.

[0075] A further benefit of toroidal shaped ceramic current cable traps is that they are easier to manufacture. Furthermore, each toroidal current cable trap can be supplied fully assembled and placed on the cable prior to the overmolding process (thus, no assembly is performed on site).

[0076] Fig.17 A flow chart of a method 248 for making a toroidal current cable trap or balun having a ceramic body is depicted. One or more steps may be performed simultaneously or in parallel. Fig.17 The depicted different orders are executed.

[0077] Method 248 includes forming a ceramic toroidal body (frame 250). The ceramic toroidal body has a first end and a second end. Forming the ceramic toroidal body includes forming a plurality of grooves in the surface of the ceramic toroidal body between the first end and the second end. The grooves extend along both the inner surface and the outer surface of the ceramic toroidal body between the first end and the second end. In certain embodiments, forming the ceramic toroidal body includes forming the ceramic toroidal body as a single part. In certain embodiments, forming the ceramic toroidal body includes forming a first half of the ceramic toroidal body and forming a second half of the ceramic toroidal body (wherein the halves of the ceramic toroidal body are configured to couple (e.g., snap) together). In certain embodiments, the ceramic toroidal body is formed via manufacturing. In certain embodiments, the ceramic toroidal body is formed via molding. In certain embodiments, the ceramic toroidal body is additively manufactured (e.g., 3D printed). Ceramic 3D printing can utilize powder sintering. For example, ceramic powder can be used to print the ceramic toroidal body. Other types of ceramic 3D printing that can be utilized include extrusion, binder jetting, nanoparticle jetting, and photopolymerization. The ceramic material used to form the ceramic torus body may be aluminum oxide, zirconium oxide, aluminum nitride, silicon carbide, silicon nitride, or other ceramic materials. When the ceramic torus body is printed, it may be placed in a dryer for drying and then fired to harden the ceramic torus body. After the ceramic torus body is formed, it may be cleaned by sandblasting.

[0078] In some embodiments, method 248 also includes disposing one or more insulating layers (of one or more different insulating materials) within the groove of the ceramic toroidal body (block 252). The one or more insulating layers will be disposed between the surface of the ceramic toroidal body in the groove and the conductor.

[0079] Method 248 also includes forming a conductive trace in the groove of the ceramic toroidal body (frame 254). In certain embodiments, the conductive trace is formed directly on the bottom surface of the groove. In certain embodiments, the conductive trace is formed on one or more insulating layers, and the one or more insulating layers are disposed in the groove. In certain embodiments, forming the conductive trace in the groove includes performing metallization to form the conductive trace in the groove of the ceramic toroidal body. In certain embodiments, a mask can be used to form the conductive trace in the groove. In certain embodiments, a vacuum deposition technique can be used to form the conductive trace in the groove. Examples of vacuum deposition techniques include silk (flash) evaporation, electron beam evaporation, induction evaporation, and sputtering.

[0080] In some embodiments, method 248 even includes disposing one or more capacitors on the ceramic toroidal body to couple them to one or more conductive traces (block 256). In some embodiments, one or more capacitors may be disposed (e.g., soldered) directly (e.g., in series) on one or more conductive traces. In some embodiments, the capacitors may be located on a printed circuit board. In some embodiments, a printed circuit board with capacitors may be disposed in a recess adjacent to a groove in the ceramic toroidal body, wherein the capacitors may be coupled to the conductive traces. When the ceramic toroidal body is formed, the recess may be formed with the groove. In some embodiments, a printed circuit board with capacitors may be disposed in a recess in a side surface of a groove located in the ceramic toroidal body, wherein the capacitors may be coupled to the conductive traces. When the ceramic toroidal body is formed, the recess in the side surface of the groove may be formed with the groove.

[0081] Fig.18 and Fig.19 Schematic diagrams of different views of a portion of a current cable trap 192 having parallel grooves with corresponding conductors are depicted. In certain embodiments, a ceramic toroidal body 258 (as described above) may include a pair of parallel grooves 260 formed therein that extend around the length of the ceramic toroidal body 258. A corresponding conductor 262 (as described above) is disposed in the corresponding grooves 260. Although not shown, in certain embodiments, a corresponding insulator may also be disposed within the grooves 260. Walls or dividers 264 are disposed between the grooves 260. In certain embodiments, one of the pair of parallel grooves 260 may include a break or gap 266 in the corresponding conductor 262 to segment the corresponding conductor 262. The corresponding conductor 262 may include one or both of these gaps 266. The gaps 266 create resonance. The pair of parallel grooves 260 with the corresponding conductors 262 function similarly to a twinax line.

[0082] Technical effects of the subject matter disclosed in the present invention include providing a balun or current cable trap having a ceramic toroidal configuration. Technical effects of the subject matter disclosed in the present invention also include manufacturing the ceramic toroidal cable trap so that the shape of the ceramic toroidal cable trap is very consistent and is not significantly affected by temperature or stress (e.g., caused by bending of the cable to which the current cable trap is coupled). Manufacturing the ceramic toroidal current trap is simpler and does not require winding a conductor around a body or structure to create an inductance. The ceramic toroidal cable trap is consistent in construction and has a smaller shape than a typical current cable trap, reducing the possibility of local heating. Technical effects of the subject matter disclosed in the present invention also include having the combined performance of multiple ceramic toroidal cable traps that produce common mode current suppression along system cables and internal coil cable wiring. In addition to reducing the risk of patient burns, another technical effect of the subject matter disclosed in the present invention includes reducing overall coil heating, making the coil safer without requiring as much insulation material. This makes the cable safer and lighter. In certain embodiments, the technical effects of the subject matter disclosed herein (e.g., when the ceramic toroidal body has two halves) also include improved maintainability due to the split construction of the individual current cable traps, which can be removed and replaced individually along the cable. The technical effects of the subject matter disclosed herein make it possible to reduce the work time for assembling the current cable (e.g., faster cable assembly time due to minimized tuning or finishing) and reduce material costs (e.g., because no internal material is required within the coil).

[0083] The technology presented and claimed herein is referred to and applied to physical and specific examples of a practical nature that clearly improves upon the present state of the art and, therefore, is not abstract, intangible, or purely theoretical. In addition, if any claim appended to the end of this specification contains one or more elements designated as "means for [performing] the function of ..." or "steps for [performing] the function of ...," it is intended that such elements be interpreted in accordance with 35 USC 112(f). However, for any claim containing elements designated in any other manner, it is not intended that such elements be interpreted in accordance with 35 USC 112(f).

[0084] This written description uses examples to disclose the subject matter, including the best mode, and also to enable those skilled in the art to practice the subject matter, including making and using any devices or systems and performing any included methods. The patentable scope of the subject matter is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insignificant differences from the literal language of the claims.

Claims

1. A current cable trap, the current cable trap comprising: a ceramic toroidal body having a first end and a second end, wherein the ceramic toroidal body includes a groove disposed on a surface of the ceramic toroidal body and extending between the first end and the second end; as well as A conductive trace is formed within the trench. 2 . The current cable trap of claim 1 , wherein the current cable trap together with the groove is additively manufactured.

3. The current cable trap of claim 2, wherein the conductive trace is formed within the trench via a metallization process.

4. The current cable trap of claim 1, wherein the groove extends along both the inner and outer surfaces of the ceramic toroidal body between the first and second ends.

5. The current cable trap of claim 1, wherein the conductive trace is disposed below an outermost surface of the ceramic toroidal body adjacent to the groove.

6. The current cable trap of claim 1, further comprising an insulating layer disposed within each of the grooves between a corresponding conductive trace and the surface of the ceramic toroidal body.

7. The current cable trap of claim 1, further comprising one or more capacitors disposed on the ceramic toroidal body and configured to tune the current cable trap to a desired frequency.

8. The current cable trap of claim 7, wherein at least one of the conductive traces is segmented into at least two segments, and at least one of the one or more capacitors is disposed between and coupled to the at least two segments within one of the grooves.

9. The current cable trap of claim 7, wherein the ceramic toroidal body includes at least one recessed portion formed adjacent to at least one of the grooves, and at least one of the one or more capacitors is disposed within the at least one recessed portion and coupled to one of the conductive traces.

10. The current cable trap of claim 1, wherein the ceramic toroidal body is formed as a single piece.

11. The current cable trap of claim 1 , wherein the ceramic toroidal body is formed in two halves configured to be coupled together around a cable to form the ceramic toroidal body configured to surround the cable.

12. The current cable trap of claim 1, wherein the groove is disposed parallel to a longitudinal axis of the ceramic toroidal body extending between the first end and the second end.

13. The current cable trap of claim 1, wherein the groove is disposed at an angle greater than zero degrees relative to a longitudinal axis of the ceramic toroidal body extending between the first end and the second end.

14. The current cable trap of claim 1, wherein the current cable trap is configured to be insensitive to detuning due to temperature changes.

15. A method for manufacturing a current cable trap, the method comprising: forming a ceramic toroidal body having a first end and a second end, wherein the ceramic toroidal body includes a groove disposed on a surface of the ceramic toroidal body and extending between the first end and the second end, and wherein the groove extends along both an inner surface and an outer surface of the ceramic toroidal body between the first end and the second end; as well as Metallization is performed to form conductive traces within the trenches.

16. The method of claim 15, wherein forming the ceramic torus body comprises additive manufacturing the ceramic torus body.

17. The method of claim 15, further comprising disposing an insulating layer within each of the grooves between a corresponding conductive trace and the surface of the ceramic toroidal body.

18. The method of claim 15, wherein the ceramic torus body is formed as a single piece.

19. The method of claim 15, wherein the ceramic toroidal body is formed in two halves configured to be coupled together around a cable to form the ceramic toroidal body configured to surround the cable.

20. A cable for a radio frequency receive coil assembly configured for use with a magnetic resonance imaging system, the cable comprising: a plurality of current cable traps disposed around the cable, wherein each current cable trap of the plurality of current cable traps comprises: an additively manufactured ceramic torus body having a first end and a second end, wherein the additively manufactured ceramic torus body includes a groove disposed on a surface of the additively manufactured ceramic torus body and extending between the first end and the second end; and a conductive trace formed within the trench via metallization; and Each current cable trap of the plurality of current cable traps is configured to be insensitive to detuning due to temperature changes.

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