Magnetic resonance imaging safe magnet structure and cochlear implant including same

Abstract

This cochlear implant includes a neural stimulator that stimulates the auditory nerve connected to the cochlea. The neural stimulator includes: a first coil unit that receives power, data, or both from an external apparatus; a first magnet unit attached to the external apparatus by magnetic force and including two or more pairs of stimuli (magnetic poles) arranged so as to have magnetic fields that cancel out each other; a neural stimulation processing unit that processes neural stimulation signals; and a neural stimulation electrode that stimulates the auditory nerve on the basis of the neural stimulation signals.

Description

Magnetic structure safe for magnetic resonance imaging and artificial cochlea including the same

[0001] A safe magnetic structure and an artificial cochlea including the same are provided for magnetic resonance imaging.

[0002] A cochlear implant is a medical device used for patients with hearing loss or impairment. It typically consists of a neural stimulator and a sound processor. The sound processor collects external sounds, processes them, and transmits them to the neural stimulator. The neural stimulator is an implanted device that stimulates the auditory nerve. A neural stimulator electrode connected to one end of the implanted neural stimulator is inserted into the cochlea. Through this electrode, the neural stimulator stimulates the auditory nerve and transmits sound signals.

[0003] A cochlear implant's neural stimulator includes an electronic circuit, a coil, and a magnet. The coil of the neural stimulator receives sound signals processed by the sound processor and power through an inductive link with the coil of the sound processor, which drives the electronic circuit and transmits neural stimulation to the auditory nerve. Since the coil of the neural stimulator receives signals and power from the coil of the sound processor to operate, magnets are used in both the neural stimulator and the sound processor to align the two coils and attach the sound processor close to the neural stimulator. The magnets in the neural stimulator of a cochlear implant are typically neodymium magnets. Neodymium magnets can generate strong magnetic fields, so they attract the magnets located in the sound processor, securing the sound processor in place and aligning the coil structure to increase the efficiency of the inductive link.

[0004] The coil of the neurostimulator receives an inductive link signal transmitted from the sound processor and generates a signal for neurostimulation. The signal received by the coil is converted into a neurostimulation signal through the neurostimulator's electronic circuitry, and this generated neurostimulation signal is transmitted to the auditory nerve via the neurostimulation electrode.

[0005] However, the magnets in cochlear implant neurostimulators can pose significant risks to patients undergoing magnetic resonance imaging (MRI). MRI uses powerful magnetic fields to image internal structures within the body, and the magnets in cochlear implant neurostimulators can shift within the body due to the MRI magnetic field. For example, the magnets in cochlear implant neurostimulators can shift within the body due to the attractive and repulsive forces of electromagnetic forces, rotate within the body due to torque, or become erect enough to lift the patient's skin. This movement of the magnets can not only damage the neurostimulator but also pose significant risks to the patient, and can also reduce the efficiency of the inductive link with the sound processor.

[0006] Accordingly, ensuring the safety of cochlear implants in an MRI environment is a key issue in the cochlear implant industry. To enhance the safety and stability of cochlear implants in an MRI environment, currently commercially available cochlear implants utilize magnets designed to minimize the generation of attractive, repulsive, and torque forces on the neurostimulator magnet during MRI. Alternatively, measures are taken to physically compress and restrain the area where the neurostimulator is implanted to prevent the magnet from moving during MRI.

[0007] Conventional cochlear implants are fixed using magnets that are magnetized with N / S or S / N poles on the side facing the skin and the side opposite to it, respectively. However, according to this magnet structure, the magnet of the cochlear implant's nerve stimulator may become upright due to the characteristic of the magnet at the center of the MR device to align in the direction of the magnetic field. To prevent the magnet from becoming upright, cochlear implants with rotating magnets are being developed. However, cochlear implants with such rotating magnets may experience reduced adhesion between the sound processor and the nerve stimulator, which may cause discomfort in cochlear implant users' daily lives. Furthermore, in conventional cochlear implants, there is a trade-off between the safety of the cochlear implant in an MR environment and the adhesion between the sound processor and the nerve stimulator.

[0008] Furthermore, because the magnet of a conventional cochlear implant's neurostimulator is structured so that it is located only at the center of the coil, mutual inductance occurs between the magnet and the coil, which can cause power loss and reduce power efficiency. Consequently, some of the electrical energy transmitted from the sound processor to the neurostimulator may be transmitted not only to the coil of the neurostimulator but also to the magnet of the neurostimulator, resulting in power loss.

[0009] In this regard, Korean Patent No. 10-2195014 discloses an external sound processing device for a cochlear implant system, Korean Patent No. 10-1488480 discloses a cochlear implant device, U.S. Patent Publication No. 2019-0239007 discloses Reversible Magnets, and U.S. Patent Publication No. 2020-0238088 discloses Cochlear Implants and Magnets.

[0010] One embodiment is to maintain patient safety and stability of cochlear implants even in an MR (Magnetic Resonance) environment, while at the same time increasing the attachment strength of external devices and neurostimulators.

[0011] One embodiment is to wirelessly transmit power and data with high efficiency while maintaining patient safety and stability of the cochlear implant even in an MR environment.

[0012]

[0013] According to one embodiment, a cochlear implant includes a neural stimulator that stimulates an auditory nerve connected to a cochlea, the neural stimulator including a first coil unit that receives power, data, or both from an external device, a first magnet unit that is magnetically attached to an external apparatus and includes two or more pairs of magnetic poles arranged to have mutually canceling magnetic fields, a neural stimulation processing unit that processes a neural stimulation signal, and a neural stimulation electrode that stimulates the auditory nerve based on the neural stimulation signal.

[0014] The first magnet portion may extend in one direction from the center of the first coil portion to the periphery.

[0015] The external device may include a second coil portion connected to the first coil portion in an inductive link manner, and a second magnet portion attached to the first magnet portion.

[0016] The first coil portion and the second coil portion may be positioned to overlap each other.

[0017] The second magnet section can be located at the center of the second coil section.

[0018] The two or more pairs of stimuli may include a first SN pole in the upper and lower direction located at the center of the first coil portion, and one or more NS poles located at the periphery of the first coil portion.

[0019] The magnetic fields of the first SN pole and one or more NS poles can cancel each other out.

[0020] One or more NS poles may be positioned around the first coil section at arbitrary angles with the first SN pole as the center.

[0021] The first magnet unit can be separated from or inserted into the neurostimulator.

[0022] A magnetic structure for an artificial cochlea according to one embodiment comprises a first coil portion located inside a nerve stimulator that stimulates an auditory nerve connected to a cochlea, the first coil portion receiving power, data, or both from an external device, and a first magnet portion extending in one direction from a center of the first coil portion to a periphery, the first magnet portion including two pairs of magnets that are magnetically attached to the external device and arranged to have magnetic fields that cancel each other out.

[0023] In one embodiment, the patient's safety and the cochlear implant's stability can be maintained even in an MR environment, while simultaneously enhancing the attachment strength of external devices and neurostimulators. Furthermore, in one embodiment, the patient's safety and the cochlear implant's stability can be maintained even in an MR environment, while simultaneously enabling high-efficiency wireless power and data transmission.

[0024] FIG. 1a is a schematic diagram illustrating an artificial cochlea according to one embodiment, and FIG. 1b is a schematic diagram illustrating hardware of a neural stimulation processing unit according to one embodiment.

[0025] FIG. 2 is a schematic diagram of a neural stimulator of an artificial cochlea according to one embodiment.

[0026] FIG. 3a is a perspective view schematically showing the neurostimulator illustrated in FIG. 2, FIG. 3b is a cross-sectional view schematically showing the neurostimulator illustrated in FIG. 3a, and FIG. 3c is an exploded perspective view schematically showing the neurostimulator illustrated in FIG. 3a.

[0027] FIG. 4a is a perspective view schematically showing a neurostimulator of an artificial cochlea according to one embodiment, FIG. 4b is a cross-sectional view schematically showing the neurostimulator shown in FIG. 4a, and FIG. 4c is an exploded perspective view schematically showing the neurostimulator shown in FIG. 4a.

[0028] FIG. 5a is a perspective view schematically showing a neurostimulator of an artificial cochlea according to one embodiment, FIG. 5b is a cross-sectional view schematically showing the neurostimulator shown in FIG. 5a, and FIG. 5c is an exploded perspective view schematically showing the neurostimulator shown in FIG. 5a.

[0029] FIG. 6a is a schematic diagram of a neural stimulator of an artificial cochlea according to one embodiment.

[0030] FIG. 6b is a schematic drawing of a neural stimulator of an artificial cochlea according to one embodiment, and FIG. 6c is a cross-sectional view schematically showing the neural stimulator illustrated in FIG. 6b.

[0031] FIG. 7a is a schematic drawing showing a subject wearing an artificial cochlear implant according to one embodiment entering an MRI environment, and FIG. 7b is a schematic drawing showing a subject wearing an artificial cochlear implant according to a conventional technique entering an MRI environment.

[0032] Figure 8 is a schematic diagram illustrating a simulation of the MRI environment illustrated in Figures 7a and 7b.

[0033] FIG. 9a is a graph measuring electromagnetic force according to the position of a subject within an MRI environment by performing a simulation of the MRI environment illustrated in FIG. 7a, and FIG. 9b is a graph measuring electromagnetic force according to the position of a subject within an MRI environment by performing a simulation of the MRI environment illustrated in FIG. 7b.

[0034] Fig. 10a is a graph measuring torque according to the position of a subject within an MRI environment by performing a simulation of the MRI environment illustrated in Fig. 7a, and Fig. 10b is a graph measuring torque according to the position of a subject within an MRI environment by performing a simulation of the MRI environment illustrated in Fig. 7b.

[0035] FIG. 11a is a drawing for measuring the adhesive force of an artificial cochlea according to an embodiment illustrated in FIG. 7a, and FIG. 11b is a drawing for measuring the adhesive force of an artificial cochlea according to the conventional technology illustrated in FIG. 7b.

[0036] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily practice the present invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein. In the drawings, parts irrelevant to the description are omitted to clearly explain the present invention, and the same reference numerals are used throughout the specification for identical or similar components. In addition, detailed descriptions of widely known and publicly known technologies are omitted.

[0037] Throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0038] Throughout the specification, expressions in the singular may be interpreted as being singular or plural, unless explicit expressions such as “one” or “single” are used.

[0039] Throughout the specification, terms containing ordinal numbers, such as "first" and "second," may be used to describe various components, but these components are not limited by the terms containing ordinal numbers. Terms containing ordinal numbers are used solely to distinguish one component from another. For example, without departing from the scope of the present disclosure, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component."

[0040] Throughout the specification, the devices that make up the network may be implemented in hardware, software, or a combination of hardware and software.

[0041] Throughout the specification, terms such as “……part”, “……unit”, “……module”, etc. mean a unit that processes at least one function or operation, which may be implemented by hardware, software, or a combination of hardware and software.

[0042] Throughout the specification, devices are configured as hardware, including at least one processor, memory device, communication device, etc., and programs or software are stored in a designated location in conjunction with the hardware and executed. The hardware has a configuration and performance capable of executing a method according to an embodiment. The program or software includes instructions implementing an operating method according to an embodiment described with reference to the drawings, and executes an embodiment in conjunction with hardware such as a processor and memory device.

[0043] Throughout the specification, “transmitting or providing” may include not only direct transmission or providing, but also indirect transmission or providing via another device or by using a bypass route.

[0044] Throughout the specification, in the flowcharts illustrated with reference to the drawings, the order of operations may be changed, several operations may be merged, some operations may be split, and certain operations may not be performed.

[0045] Then, the magnetic resonance stability magnetic structure and the artificial cochlea including the same will be described in detail.

[0046] FIG. 1a is a schematic diagram illustrating an artificial cochlea according to one embodiment, and FIG. 1b is a schematic diagram illustrating hardware of a neural stimulation processing unit according to one embodiment.

[0047] Referring to FIG. 1A, a cochlear implant includes a neural stimulator (100) that stimulates the auditory nerve and an external apparatus (200) that is located outside the human body and communicates with the neural stimulator (100). For example, the external apparatus (200) may perform a sound processing function that processes external sounds and transmits them to the neural stimulator (100). In addition, the neural stimulator (100) may include a sound processing function that processes external sounds.

[0048] A neural stimulator (100) can be implanted inside a human body (10) and stimulates an auditory nerve connected to a cochlea (500). The neural stimulator (100) includes a first coil unit (110), a first magnet unit (120), a neural stimulation processing unit (130), and a neural stimulation electrode (140). An external device (200) can be located outside the human body (10). The external device (200) includes a second coil unit (210), a second magnet unit (220), a signal processing unit (230), and a power supply unit (240). In addition, if the nerve stimulator (100) includes a sound processing function for processing sounds from outside, the signal processing unit (230) may be built into the nerve stimulator (100).

[0049] The first coil unit (110) and the second coil unit (210) are connected to each other in an inductive link manner to wirelessly transmit and receive power, data, or both. In addition, the first magnet unit (120) and the second magnet unit (220) may be attached to each other by magnetic force. The first magnet unit (120) includes one or more magnets, and the one or more magnets include two or more pairs of magnetic poles so as to have mutually canceling magnetic fields, so that movement of the cochlear implant can be suppressed even in an MR (Magnetic Resonance) environment, thereby maximizing the safety of the patient and the stability of the cochlear implant. In addition, the first magnet unit (120) may have a structure that extends in one direction from the center to the periphery of the first coil unit (110). For example, the first magnet part (120) attached to the second magnet part (220) is positioned inside the neurostimulator (100) so that the centers of the first coil part (110) and the second coil part (210) overlap each other. Accordingly, the transmission and reception efficiency of power and data by the inductive link can be maximized. The relative positions of one or more magnets in the first magnet part (120) are fixed, and accordingly, the magnets can be prevented from rotating or moving to positions where their magnetic fields do not cancel each other out.

[0050] For example, sound collected through a microphone can be converted into a digital signal through a signal processing unit (230), amplified, and transmitted to the second coil unit (210). The power supply unit (240) supplies power to drive the external device (200) and applies power to the signal processing unit (230) and the second coil unit (210). The second coil unit (210) transmits voice data received from the signal processing unit (230) to the first coil unit (110) in an inductive link manner, and transmits power received from the power supply unit (240) to the first coil unit (110) in an inductive link manner.

[0051] The power received through the first coil unit (110) drives the nerve stimulator (100). In addition, the voice data received through the first coil unit (110) is converted into a nerve stimulation signal by the operation of the nerve stimulation processing unit (130) and transmitted to the nerve stimulation electrode unit (140). Accordingly, the nerve stimulation electrode unit (140) located inside the cochlea (150) stimulates the cochlea (150) based on the nerve stimulation signal, thereby stimulating the auditory nerve connected to the cochlea and allowing the subject to recognize sound.

[0052] Referring to FIG. 1B, the neurostimulation processing unit (130) may be implemented with at least one computing device and may execute a computer program including instructions described to perform an operation according to one embodiment. The hardware of the neurostimulation processing unit (130) may include one or more processors (131), one or more memories (133), one or more storages (135), and one or more communication interfaces (137), which may be connected to each other via a bus. In addition, the hardware of the neurostimulation processing unit (130) may include hardware such as input devices and output devices. In addition, the neurostimulation processing unit (130) may be equipped with various software including an operating system capable of running a program. In addition, the neurostimulation processing unit (130) may be implemented with one or more chips.

[0053] The processor (131) is a device that controls the operation of the nerve stimulation processing unit (130), and may be various types of processors that process commands included in the program. For example, the processor (131) may be a CPU (Central Processing Unit), an MPU (Micro Processor Unit), an MCU (Micro Controller Unit), a GPU (Graphics Processing Unit), etc. The memory (133) loads the corresponding program so that commands described to execute an operation according to an embodiment are processed by the processor (131). For example, the memory (133) may be a ROM (read only memory), a RAM (random access memory), etc. The storage (135) stores various data, programs, etc. required to execute an operation according to an embodiment. The communication interface (137) is a wired / wireless communication module, and can be linked with an external database through a wired / wireless network.

[0054] Additionally, the signal processing unit (230) of the external device (200) may be implemented as at least one computing device, and may include one or more processors, one or more memories, one or more storages, and one or more communication interfaces, which may be interconnected via a bus. Accordingly, the description of the signal processing unit (230) is applied in the same manner as the aforementioned description of the neurostimulation processing unit (130).

[0055] FIG. 2 is a schematic drawing of a neural stimulator of an artificial cochlea according to one embodiment, FIG. 3a is a perspective view schematically illustrating the neural stimulator illustrated in FIG. 2, FIG. 3b is a cross-sectional view schematically illustrating the neural stimulator illustrated in FIG. 3a, and FIG. 3c is an exploded perspective view schematically illustrating the neural stimulator illustrated in FIG. 3a.

[0056] Referring to FIGS. 2 and 3a to 3c, the neurostimulator (100) includes a first coil unit (110), a first magnet unit (120), a neurostimulation processing unit (130), a neurostimulation electrode unit (140), and a housing (190) containing these. The description of FIGS. 1a and 1b described above also applies equally to the neurostimulator (100) of FIGS. 2 and 3a to 3c.

[0057] The first magnet portion (120) can be inserted into or separated from the interior of the housing (190) through a side opening (199) formed on the side of the housing (190). The housing (190) can be made of a silicone material. The first magnet portion (120) includes one or more magnets in which two or more pairs of magnetic poles (121, 122, 123, 124) are arranged to have magnetic fields that cancel each other out. The two pairs of magnetic poles (121, 122, 123, 124) are composed of a first magnet (121, 123) and a second magnet (122, 124). For example, the first pole (121) can be composed of a south pole, the second pole (122) of a north pole, the third pole (123) of a north pole, and the fourth pole (124) of a south pole. In this case, the magnetic fields of the first magnet (121, 123) and the second magnet (122, 124) can cancel each other out. In addition, the magnetic fields of the first pole (121) and the third pole (123) and the magnetic fields of the second pole (122) and the fourth pole (124) can cancel each other out. The magnets composed of two pairs of magnetic poles (121, 122, 123, 124) are placed in grooves formed in the upper case (128) and the lower case (129), and the upper case (128) and the lower case (129) are coupled to each other. In this way, since the first magnet (121, 123) and the second magnet (122, 124) are fixed inside the housing (190), the first magnet (121, 123) and the second magnet (122, 124) can be prevented from rotating or moving to a position where their magnetic fields do not cancel each other out. The side protrusion portion (127) formed at one end of the upper case (128) is seated in the side opening (199) of the housing (190), and can be made to allow the first magnet portion (120) to be easily inserted and removed.

[0058] The first magnet (121, 123) may be positioned at the center of the first coil portion (110). Accordingly, the first magnet (121, 123) may be attached by magnetic force to the second magnet portion (220) positioned at the center of the second coil portion (210) of the external device (200). In addition, by attaching the first magnet (121, 123) and the second magnet portion (220), the first coil portion (110) and the second coil portion (210) overlap each other, so that the transmission and reception efficiency of power and data may be maximized. Furthermore, referring to FIG. 3b, the first magnet portion (120) is tilted toward the upper center of the housing (190) so that the first magnet (121, 123) is positioned above the second magnet (122, 124). Accordingly, the distance between the first magnet (121, 123) and the second magnet (220) becomes closer, increasing the adhesive force, and the size of the housing (190) becomes smaller, enabling miniaturization of the nerve stimulator (100).

[0059] FIG. 4a is a perspective view schematically showing a neurostimulator of an artificial cochlea according to one embodiment, FIG. 4b is a cross-sectional view schematically showing the neurostimulator shown in FIG. 4a, and FIG. 4c is an exploded perspective view schematically showing the neurostimulator shown in FIG. 4a.

[0060] Referring to FIGS. 4A to 4C, the neurostimulator (100) includes a first coil portion (110), a first magnet portion (120), and a housing (190) containing them. The description of FIGS. 1A to 3C described above is mostly applied to the neurostimulator (100) of FIGS. 4A to 4C. However, in the case of the neurostimulator (100) of FIGS. 4A to 4C, a bottom opening (198) is formed on the lower surface of the housing (190), and when the housing (190) is lifted in the direction of arrow ①, the first magnet portion (120) can be separated or inserted through the bottom opening (198) in the direction of arrow ②.

[0061] FIG. 5a is a perspective view schematically showing a neurostimulator of an artificial cochlea according to one embodiment, FIG. 5b is a cross-sectional view schematically showing the neurostimulator shown in FIG. 5a, and FIG. 5c is an exploded perspective view schematically showing the neurostimulator shown in FIG. 5a.

[0062] Referring to FIGS. 5A to 5C, the neurostimulator (100) includes a first coil portion (110), a first magnet portion (120), and a housing (190) containing them. The description of FIGS. 1A to 3C described above is mostly applied to the neurostimulator (100) of FIGS. 5A to 5C. However, in the case of the neurostimulator (100) of FIGS. 5A to 5C, a top opening (197) is formed on the upper surface of the housing (190), and the first magnet portion (120) can be separated or inserted through the top opening (197) by lifting the ring portion (126) formed at one end of the upper case (128) in the direction of arrow ①.

[0063] FIG. 6a is a schematic diagram of a neural stimulator of an artificial cochlea according to one embodiment.

[0064] Referring to FIG. 6a, the neurostimulator (100) includes a first coil portion (110), a first magnet portion (120), a neurostimulation processing portion (130), a neurostimulation electrode portion (140), and a housing containing them. The descriptions of FIGS. 1a and 1b and of FIGS. 2 and 3a to 3c are mostly equally applied to the neurostimulator (100) of FIG. 6. However, the first magnet portion (120) of the neurostimulator (100) of FIG. 6 is at a position rotated 90 degrees clockwise from the first magnet portion (120) of the neurostimulator (100) of FIG. 2. In addition, the first magnet part (120) may be at a position rotated from 0 to 360 degrees clockwise, and in this case, since the first magnet (121, 123) is located at the center of the first coil part (110), the second magnet part (220) located at the center of the second coil part (210) is attached to the first magnet (121, 123) by magnetic force, so that the centers of the first coil part (110) and the second coil part (210) can coincide with each other. Accordingly, the efficiency of wireless transmission and reception of power and data between the coils can be maximized. In addition, even if the external device (200) rotates during the process of being attached to the neurostimulator (100), the wireless transmission and reception of power and data between the coils can be maintained constantly. In addition, the first magnet part (120) may include a first SN pole in the vertical direction located at the center of the first coil part (110), and one or more NS poles located on the periphery of the first coil part. For example, the first magnet part (120) may further include a third magnet located 180 degrees symmetrically with respect to the second magnet (122, 124) with respect to the first magnet (121, 123), and in this case, the first magnet (121, 123), the second magnet (122, 124), and the third magnet have magnetic fields that cancel each other out. In addition, the first magnet part (120) may include a plurality of NS poles located on the periphery of the first coil part (110) at intervals of an arbitrary angle with respect to the first SN pole in the vertical direction as the center.For example, the first magnet part (120) may include three pairs of NS poles positioned at 120-degree intervals around the circumference of the first coil part (110) with the first SN pole in the vertical direction as the center.

[0065] FIG. 6b is a schematic drawing of a neural stimulator of an artificial cochlea according to one embodiment, and FIG. 6c is a cross-sectional view schematically showing the neural stimulator illustrated in FIG. 6b.

[0066] Referring to FIGS. 6b and 6c, the neurostimulator (100) includes a first coil portion (110), a first magnet portion (120), and a housing containing them. The descriptions of FIGS. 1a and 1b and FIGS. 2 and 3a to 3c described above are mostly equally applicable to the neurostimulator (100) of FIGS. 6b and 6c. However, unlike the first coil portion (110) of FIG. 3b, which is configured entirely in a flat plate shape, a part of the first coil portion (110) of the neurostimulator (100) of FIGS. 6b and 6c is configured in a laminated shape. Accordingly, more space is secured inside the housing where the first magnet portion (120) is arranged, so that the first magnet portion (120) can use a thicker magnet that increases magnetic force. Additionally, the first magnet portion (120) can be positioned closer to the subject's skin, thereby increasing the adhesion to the external device (200).

[0067] FIG. 7a is a schematic diagram showing a subject wearing an artificial cochlear implant according to one embodiment entering an MRI environment, FIG. 7b is a schematic diagram showing a subject wearing an artificial cochlear implant according to a prior art entering an MRI environment, and FIG. 8 is a schematic diagram showing a simulation of the MRI environment shown in FIGS. 7a and 7b.

[0068] The artificial cochlea shown in Fig. 7a is the artificial cochlea of ​​Figs. 2 to 3c described above. The conventional artificial cochlea shown in Fig. 7b is an artificial cochlea configured with a rotating magnet to prevent the magnet from standing upright.

[0069] Referring to FIGS. 7a, 7b, and 8, an MRI with a width of 0.44 m, a length of 0.2 m, and a magnetic flux density of 3 T is used, and the arrows inside the MRI represent magnetic field vectors.

[0070] FIG. 9a is a graph measuring electromagnetic force according to the position of a subject within an MRI environment by performing a simulation of the MRI environment illustrated in FIG. 7a, and FIG. 9b is a graph measuring electromagnetic force according to the position of a subject within an MRI environment by performing a simulation of the MRI environment illustrated in FIG. 7b.

[0071] In the graphs of FIGS. 9A and 9B, the x-axis represents the distance from the center, with the center inside the MRI set as 0 mm, and the y-axis represents the electromagnetic force. Referring to FIGS. 9A and 9B, the electromagnetic force received by the cochlear implant in the x, y, and z directions of the MRI environment when the subject passes through the MRI is shown. The electromagnetic force received by the cochlear implant according to one embodiment at the entrance and exit of the MRI is reduced by approximately 50% compared to the electromagnetic force received by the cochlear implant according to the prior art.

[0072] Fig. 10a is a graph measuring torque according to the position of a subject within an MRI environment by performing a simulation of the MRI environment illustrated in Fig. 7a, and Fig. 10b is a graph measuring torque according to the position of a subject within an MRI environment by performing a simulation of the MRI environment illustrated in Fig. 7b.

[0073] In the graphs of FIGS. 10A and 10B, the x-axis represents the distance from the center, with the center inside the MRI being 0 mm, and the y-axis represents the torque. Referring to FIGS. 10A and 10B, the torque received by the cochlear implant in the x, y, and z directions of the MRI environment when the subject passes through the MRI is shown. The torque received by the cochlear implant according to one embodiment when passing through the MRI is almost canceled. However, since the torque received by the cochlear implant according to the prior art when passing through the MRI is not canceled, the cochlear implant implanted in the subject's body may be aligned in the direction of the magnetic field inside, which may cause a risk.

[0074] FIG. 11a is a drawing for measuring the adhesive force of an artificial cochlea according to an embodiment illustrated in FIG. 7a, and FIG. 11b is a drawing for measuring the adhesive force of an artificial cochlea according to the conventional technology illustrated in FIG. 7b.

[0075] In Fig. 11a, the nerve stimulator (100) is tilted at about 3.5 degrees, the magnetic flux density of the magnet of the nerve stimulator (100) is 226 mT, the magnetic flux density of the magnet of the external device (200) is 469 mT, and the measured adhesion force is about 0.089 N. In Fig. 11b, the nerve stimulator and the external device according to the prior art are parallel to each other, the magnetic flux density of the magnet of the nerve stimulator is 226 mT, the magnetic flux density of the magnet of the external device is 469 mT, and the measured adhesion force is about 0.08 N. Accordingly, the adhesion force of the artificial cochlea according to one embodiment is about 11.7% better than that of the artificial cochlea according to the prior art.

[0076] In one embodiment, the cochlear implant is safe in an MR examination environment by canceling out electromagnetic and torque forces, and also has enhanced adhesion. Furthermore, in one embodiment, the cochlear implant comprises two or more pairs of stimuli, with one or more stimuli arranged around the central stimulator, thereby maximizing the efficiency of wireless transmission and reception of power and data between coils.

[0077] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention.

Claims

1. Includes a neural stimulator that stimulates the auditory nerve connected to the cochlea, The above neurostimulator, A first coil unit that receives power, data, or both from an external apparatus; A first magnet unit including two or more pairs of magnetic poles that are attached to the external device by magnetic force and arranged to have magnetic fields that cancel each other out, A neural stimulation processing unit that processes neural stimulation signals, and A neural stimulation electrode that stimulates the auditory nerve based on the above neural stimulation signal Artificial cochlea containing.

2. In paragraph 1, An artificial cochlea, wherein the first magnet portion extends in one direction from the center of the first coil portion to the periphery.

3. In paragraph 2, The above external device is, A second coil part connected to the first coil part in an inductive link manner, and An artificial cochlea comprising a second magnet portion attached to the first magnet portion.

4. In paragraph 3, An artificial cochlea, wherein the first coil portion and the second coil portion are positioned to overlap each other.

5. In paragraph 3, An artificial cochlea, wherein the second magnet portion is located at the center of the second coil portion.

6. In paragraph 1, An artificial cochlea, wherein the two or more pairs of stimuli include a first SN pole in the upper and lower direction located at the center of the first coil portion, and one or more NS poles located at the periphery of the first coil portion.

7. In paragraph 6, An artificial cochlea, wherein the magnetic fields of the first SN pole and the one or more NS poles cancel each other out.

8. In paragraph 7, An artificial cochlea, wherein the one or more NS poles are positioned around the first coil section at arbitrary angles with the first SN pole as the center.

9. In paragraph 1, An artificial cochlea, wherein the first magnet part is separated from or inserted into the neurostimulator.

10. Located inside the neural stimulator that stimulates the auditory nerve connected to the cochlea, A first coil unit comprising a first coil unit that receives power, data, or both from an external apparatus, A magnetic structure for an artificial cochlea, comprising a first magnet unit that extends in one direction from the center of the first coil unit to the periphery, and includes two pairs of magnetic poles that are attached to the external device and magnetically and arranged to have magnetic fields that cancel each other out.

Images