JPH01244751A - Multiple channel electrode apparatus for implantation and production thereof - Google Patents

Abstract

PURPOSE: To provide a multi-channel electrode for implant making possible to make a deaf-and-dumb person so as to obtain an auditive sensibility by providing a plurality of lead wires arranged in the interior of a histocompatible longitudinal formed body, terminating each lead wire at respective one electrode and transmitting stimulation by electrical puls to a nerve or a muscle. CONSTITUTION: A multi-channel electrode body is provided with a silicon elastomer-made formed body and, in the formed body, a large number of lead wires 91 are buil-in. Each lead wire 91 is terminated at the globular point of contact 92 of electrode on the surface of an electrode body 90. According to the arraignment of the point of contact 92 of the electrode upon the surface of the electrode, a selective stimulation in each snail region is made possible in response to an implanted electrode within the snail, Since the lead wires 93, 94 are made wave-like for avoiding a tensile load, the electrode is easily bent when it is introduced into the snail. The point of contact of the electrode 92 is arranged against two rows opposed each other along the electrode body 90.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-channel electrode device for cochlear implantation for stimulating nerves or muscles with electrical pulses so that deaf or hearing-impaired people can have a sense of hearing; The present invention relates to a method of manufacturing a multi-channel electrode device.

An improvement to a conventional prosthetic device (hearing aid) for implantation in the mastoid, which serves to amplify sound waves, is disclosed in U.S. Pat. No. 3,209,081.
Known by No. In that case, the implanted receiver is in direct contact with the bone, from where the sound waves are guided to the inner ear by bone conduction.

Recently, devices that do not simply amplify sound waves but also convert sound waves into electrical pulses have become known. The pulses are used to electrically stimulate the auditory nerve and cause the sensation of hearing.

US Pat. No. 3,449,768 describes the use of coded pulse trains to generate electric fields with desired gradients that serve to stimulate the visual or auditory system. Further, US Pat. No. 3,752,939 describes the use of an electrode having two conductive wires on its surface over the entire length of the electrode.

Journal of the Otolaryngology Society, Vol. 103, published December 1977, in the paper by Schindler et al. [Implantation of multiple electrodes into the whorl],
Spatially localized stimulation of the cat auditory nerve has been described. Otolaryngology Annual Report 90/7. In 1976, Clark and Hallworth's article ``Multiple electrode arrays for cochlear implantation'' described a cochlear electrode with a thin film structure mounted on a flat flexible carrier material. . Other devices are known, such as thin wire bundles, which are used to provide electrical stimulation directly to the auditory nerve after it has been extracted from the whorl.

European Patent Application No. 783005671 and German Publication No. 2
No. 823,798 describes an implantable multi-channel hearing aid based on electrical stimulation of the auditory nerve, for which a circuit with active elements is used.

The invention comprises a device for transmitting a plurality of carrier signals, each modulated by a signal representing a frequency band, and a multichannel receiving device for receiving an oscillator signal,
Each receiving channel is assigned to one signal representing one frequency band of the acoustic signal, and also includes a signal applying device for applying the signal from each said receiving channel to at least one electrode contact of the multi-channel electrode. The present invention is directed to a multichannel electrode device for cochlear implantation, which is used to apply electrical stimulation via the multichannel electrode, and a method for manufacturing the same.

The multi-frequency device for improving electrical stimulation of the auditory nerve according to the invention can have a plurality of transmission channels through the skin, and a signal representing each one frequency band of the audio waveband can be transmitted through the transmission channels. is superimposed on the carrier frequency of

The multi-channel receiving device used in this type of multi-frequency device consists of a plurality of mutually independent channels, each including a coil tuned to receive a predetermined oscillator signal, and a plurality of mutually independent channels, each including a coil tuned to receive a predetermined oscillator signal, and a plurality of mutually independent channels each comprising a coil tuned to receive a predetermined oscillator signal; It includes a demodulator coupled to the coil and a coupling device for coupling the demodulated signal to the electrode contacts. Each of these receiving channels receives a respective signal transmitted wirelessly through the skin.

The present invention comprises an elongated tissue-compatible molded body, a plurality of conductive wires are disposed inside the molded body, each of the plurality of conductive wires terminates in one electrode contact, and each electrode contact is connected to the molded body. The present invention resides in a multi-channel electrode device for annular implantation, which is attached to the surface of the body and each lead is corrugated to make the electrode flexible and relieve tension loads.

The present invention also provides (a) manufacturing a plurality of conductive wires each having one contact at the tip; (b) corrugating each of the conductive wires to increase the flexibility of the electrode body; (c1) each of the contact points having a vacuum suction (d) dispensing a tissue-compatible material into the mold; It also covers methods of manufacturing channel electrode devices.

Next, further explanation will be given with reference to the accompanying drawings.

Sound waves are normally guided to the eardrum 12 by the outer ear IO,
The tympanic membrane 12 is coupled to and moves the auditory ossicles 14 of the middle ear, thereby energizing the cochlea 16. Cochlea 16 is 2.
It is a spiral formation with 5 turns. The cochlea 16 has a superior canal or scala vestibule 18 and a superior canal or scala tympani 20. Between the scala vestibuli 18 and the scala tympani 20 there is a whorl canal 22 . In both fluid-filled floors 18 and 20, the incoming sound waves create fluid waves, which generate electrical pulses by the transduction function of the inner ear, and these pulses are guided to the brain by the auditory nerve 24, where they are sensed by the sense of hearing. It is interpreted as

The inner ear of a completely deaf person cannot convert incoming sound waves into electrical signals that can be transmitted to the brain. Therefore, multi-frequency stimulators are designed to electrically stimulate the cochlea directly.

The stimulator includes a body-wearable multi-channel acoustic processing and transmitting device 30. Acoustic processing transmitter 30 is coupled to an implanted receiver. The coupling is preferably effected inductively via a coil 36.38, which is connected to a coil 32.34 and to the acoustic processing and transmitting device 30, which form part of the implanted receiving device.

As will be described in detail below, the acoustic processing transmitter 30 generates a plurality of carrier signals, on which a series of signals in an audible frequency band are superimposed. The transmitted signal is received and demodulated by an implanted receiver. The demodulated signal is fed via conductors 42, 44 to the multi-channel electrode 46 of the present invention.

Electrode 46 is implanted in the cochlea. The electrode 46 has a number of electrode contacts on its surface, which electrode contacts are used to selectively stimulate the cochlea locally, corresponding to its frequency assignment.

According to a preferred embodiment, the multi-frequency device has four channels corresponding to four frequency bands, into which the listening area is divided.

FIG. 2 is an electrical block diagram of the acoustic processing transmitting device 30, and this device 30 has a frequency of 0.25 to 0.5 KHz, 0
．． It has four channels corresponding to 5 to 1.0 KHz, 1.0 to 2.0 KHz, and 2.0 to 4.0 KHz. The configuration of each channel is shown in the form of a block diagram for channel 1. Each channel has a desired frequency band (for example, 0.25 to 0.00 for channel 1).
5 KHz).

An audible signal is supplied to the input of the filter 50 and is received by a microphone 52 and amplified by a controlled amplifier 54 . After amplifier 54 the audio signal still contains another frequency band, for example frequency band 55, but after passing through filter 50 it is limited as shown by frequency band 57. A signal delay circuit may be placed in the low frequency processing channel that simulates the time that a traveling wave across the length of the cochlea would have in a healthy ear.

Signal 57 is then fed to comparator 58, which produces a limited signal 59. This zero crossing of signal 59 is matched with the zero crossing of signal 57.

The limited signal 59 is directed to a frequency to voltage converter 60. Converter 60 generates a variable DC voltage proportional to the frequency of signal 59. The transducer 60 has suitable structural elements, for example a monostable multi-bi break, which is triggered by the signal 59 (S 59).
A pulse of the same pulse width with the same repetition frequency as the pulse from 9 is generated. The output of the multivibrator is connected to a low pass filter which generates a variable DC voltage proportional to the pulse repetition frequency.

The voltage signal at the output of converter 60 is fed to a voltage-frequency converter 62, which is a voltage-controlled oscillator. converter 6
The output signal 63 of 2 consists of a series of pulses, which have a constant pulse width and whose pulse train frequency corresponds to the voltage controlling the oscillator.

The pulse train frequency of the signal 63 is within a band consisting of, for example, 40
~400 Hz, and the bandpass filter 50 may filter out frequency bands larger or smaller.

As explained further below, the auditory nerve is best able to discriminate repetition frequencies in stimulation signals of about 400 Hz or less. This is why the frequency band filtered by bandpass filter 50 is transformed as described above into a lower frequency band that is best suited to the auditory nerve. This band is often between 40 and 400 Hz, but may be larger.

The signal at the output of the bandpass filter 50 is also guided into a series circuit of a rectifier 66 and a logarithmic amplifier 68, which produces a DC voltage that depends on the logarithm of the amplitude of the signal rectified by the rectifier 66. arise.

All channels are equipped with identical circuit elements behind different bandpass filters. The monostable multi-bibrake of each channel generates an output pulse train consisting of pulses of variable pulse width varying in amplitude repeatedly within the range of 400-400 Hz, corresponding to a frequency band particularly suitable for stimulation of the cochlea. These pulse trains are superimposed on the carrier signal at the transmitter 74.

In this four-channel embodiment, the multi-channel oscillator 74 uses four carrier signals, two of which are
2MHz, and the other two are 31MHz. channel 1
．． The pulse train of channel 2.3 is used to modulate the 12 MHz carrier signal, and the pulse train of channel 2.4 modulates the 31 MHz carrier signal.

The carrier signal, on which the signal of channel l, 2 is superimposed, is applied to one transmitter coil, and the carrier wave, on which the signal of channel 3.4 is superimposed, is applied to the second transmitter coil. Ru. Both carrier frequencies applied to the oscillator coils are therefore unequal and interaction between the channels is avoided.

However, by using this transmitter coil for two channels, the structure is simplified. However, using a dedicated oscillator coil for each channel is also advantageous for other reasons.

FIG. 3 shows a preferred configuration example of a 4-channel multichannel receiving apparatus.

Each channel has coils 81-84, coils 81 .
82 is inductively coupled to transmitter coil 76 and coils 83 .
84 is inductively coupled to transmitter coil 78. A capacitor 85 is connected in parallel to each of the coils 81 to 84, thereby forming an oscillation circuit with a resonant frequency of 12 MHz or 31 MHz.

The signal received by coil 81 is fed to a demodulator consisting of diode 86, capacitor 87 and resistor 88. In the case of pulse width modulation and demodulation, the voltage at the detector output is limited by connecting a zener diode in parallel with resistor 88. Voltage fluctuations due to changes in the coupling between the transmitter and receiver coils can thereby be minimized.

The voltage at the detector output 90 preferably moves within a range of 0 to 3 cm, and varies from 40 to 40'OH in response to the modulation signal.
It has a frequency of z.

A device for tissue stimulation with a small number of mutually independent channels activated by multiple signals at the same time, especially 2 to 9
For devices with channels, the following method may be advantageous. It is a method of arranging receiver coils in stacked groups to minimize the space demands created by the use of multiple receiver coils.

Even if each receive signal coil in a group is tuned to one specific frequency, simply arranging the coils one on top of the other will result in spacing due to the mutual inductance of the two or three receiver coils. Crosstalk that is even stronger than normal can occur. Coil 81. so that the opposing magnetic fluxes are compensated.
When 82 is arranged as shown in FIG. 4, mutual inductance disappears. As a result, two or three mutually independent channels can be obtained, which occupy less space than a single channel and have negligible crosstalk. Corresponding to this concept, in FIG. 4 the coils 81.82 and 83.84 are arranged in two mutually separate groups. These two groups represent different possibilities for arranging two coils in a group to compensate for mutual inductance. 85, 86, and 87 are 3 groups grouped together to compensate for mutual inductance.
There are two coils. The diameter of coils 85-87 is 1.5-
The distance between the two coil groups is approximately 3C11 to prevent crosstalk between the two coil groups.

The coils 81, 82 have different frequencies (e.g. 12,31
MHz), each receive channel receives and demodulates only the signal of the transmit channel to which it is assigned. The demodulated signals from each receive channel are directed to the multichannel electrode of the present invention as shown in FIG.

One or more electrode contacts 92 can be coupled to each channel, and these electrode contacts can be used in multiple channels to stimulate such defined locations along the cochlea for initial pitch perception. It is arranged along the electrode body.

When using various connection connections, bivola-stimulation, univola-stimulation to remote earth electrodes or stimulation to a common distributed earth can be used.

The multichannel electrode body of the present invention includes a molded body made of silicone elastomer, such as "silastic", and a number of conductive wires 91 are embedded inside the molded body. Each conductive wire 91 connects to a spherical electrode contact 9 on the surface of the electrode body 90.
Terminates at 2. Due to the arrangement of electrode contacts 92 on the electrode surface,
Following the implantation of electrodes in the cochlea, selective stimulation of each cochlear region is possible. As can be seen from FIG. 6, which is a schematic diagram of the human cochlea, the high frequency response area is located in the root region, and the low frequency response region is located in the apical region. A desired pitch perception is thereby obtained corresponding to the arrangement of the electrode contacts 92 within the whorl. Pitch continuity is achieved by additional stimulation frequency changes.

FIG. 7, which is a schematic cross-sectional view of the multi-channel electrode of the present invention, shows the arrangement of conductive wires inside the electrode. Only two conductors 93,94 are shown for simplicity of illustration. The conductors 93,94 are corrugated to remove tensile loads, but this facilitates bending of the electrodes during introduction into the cochlea.

According to the preferred embodiment, the conductors 93,94 have a diameter of 25
It is a µm Teflon-insulated platinum (90%)-iridium (10%) wire. The sphere at the tip of the four wires 93,94 has a diameter of 0.3 mm and is formed by flame melting the conductor wires 93,94.

The electrode contacts 92 are arranged in pairs along the electrode body 90 in two rows facing each other.

According to a preferred embodiment, the electrode body 90 has a diameter of 0.5 mm.
9 tm, decreasing to 0.5 +n towards the tip. The total length of the electrode body 90 must accommodate the introduction of 20 to 25 electrodes into the cochlea.

FIG. 8 shows one mold half 96 of two identical mold halves for producing the multichannel electrode of the present invention. The mold half 96 has a gradually narrowing groove 97 shaped into the desired electrode shape, and a number of through holes 98 are formed in the groove 97, all communicating with one vacuum conduit 99. When manufacturing a multi-channel electrode, conductive wires 93,94 are placed in the grooves 97 of the mold half. At that time, conductor 93
．． The spherical tip of 94 is positioned in the through hole 98 of the mold half 96 by vacuum action. After that, the mold 96 is assembled and the groove 9
Press fit the above-mentioned silastic material into the tube. Vacuum suction through the through holes 98 precisely positions the electrode contacts 92 on the surface of the electrode body 90 .

The electrode body 100 according to the modification shown in FIG. 9a has a curvature corresponding to the curvature in the medium.

Figure 9b shows the method of introducing the electrode body 100 into the cochlea. A straight rod, for example a copper wire, is used as the electrode body 1.
00 and is gradually pulled out while inserting the electrode body 100 into the cochlea. Thereby, the electrode body 100 returns to its original shape.

Structural forms of externally provided or internally implanted subsystems other than those described above are as follows.

b) Four or more channels of electrodes introduced into the cochlea combined with four channels of internal equipment and one channel of external sound processing and transmitting equipment.

In this case, one electrode channel for stimulation is selected or the desired number of electrode contacts are coupled together. In the latter case, different darkness values for the separate electrode contacts can be compensated for by corresponding adaptation.

o) A single channel electrode at or near the porthole, fixed in conjunction with a large earth electrode.

A ground electrode can also be attached to the outside of the cochlea. Single channel electrodes can be used with single channel internal devices and single channel external acoustic processing and transmitting devices.

The device (a) has already proven its worth in several fully deaf volunteers, and has been shown to be able to produce 60 to 60 minutes of normal conversation about unknown words or sentences using only electrical stimulation, without the need for supplementary lip reading. 70% understanding was obtained. This makes it clear that this artificial means can be seen as a useful hearing aid for all deaf people.

The device (0) is mainly used for people who are not completely deaf, that is, people with hearing loss and children with hearing problems.

In both single-channel and multi-channel external acoustic processing and transmitter systems, analog signals can be used instead of converting sound waves into pulse trains. In this case, appropriate dynamic range compression and compensation of the frequency dependence of the sound intensity become very important characteristics of the acoustic processing and transmitting device. These characteristics are important for the following reasons.

That is, the dynamic range between the stimulus values required for marginal hearing and excessive hearing is much narrower than when a person with normal hearing hears, and, moreover, in many cases, The perception of threshold and supra-limit sound intensities is highly dependent on stimulation frequency.

Non-linearities are particularly exploited for dynamic range compression. This nonlinearity may be a logarithmic or power function, may consist of an intermittent linear function, or may have any other suitable form.

Non-linearity is obtained by using suitable differential amplifiers or operational amplifiers coupled to diode-wired transistors or diode networks.

Nonlinearity can be controlled by a frequency-shifted signal so that undesired frequencies are not generated due to dynamic range compression. In this case, the even-numbered distorted wave components can be removed by a narrowband bandpass filter in the up-shifted signal, and then the signal can be mixed down-shifted back into the original audio frequency range.

Another possibility to reduce the distorted wave content is to use multiple nonlinearities within an octave wide band.

Controlled amplifiers with sufficiently low response or fall time constants of 2-10 msec or 100-300 msec may be used. Appropriate nonlinearities can be added to the signal path to give the desired shape to the amplitude characteristics of the controlled amplifier.

The dynamic range compression circuit may precede the frequency response compensation circuit. Although the amount of frequency response compensation required in this case is relatively small, this compensation must be done very accurately.

FIG. 10 shows a block diagram of a single-channel or multi-channel acoustic processing and transmitting device.

A multichannel stimulator consists of a plurality of nearly identical channels, each with a specific radio frequency transmission section. Each channel shares a predetermined audio frequency band that is filtered by a respective bandpass filter. In the case of a single channel stimulator, the bandpass filter 103 is not needed since only one channel is used. The signal received by the electret microphone 104 is 80
It has a dynamic range of more than dB. Converting this large dynamic range to a range of permissible stimulus values of about 10 dB is achieved by using the Guinamisoku compression circuit 10, which will be described in detail later.
7 and/or an input controlled counter-control acting on amplifier 105. Compared to dynamic compression using non-linear elements, this control has the advantage of less time-induced non-linear distortion, but due to the final response time, when a high-frequency signal suddenly occurs, the Since the disturbance peaks are also passed through, dynamic compression as well as control is generally used.

The adaptation circuit 106 adapts the frequency response to the pre-measured frequency dependence of the user's pitch curve.
It has frequency-dependent elements, such as RC elements or LC elements, and is connected in the usual way.

The adaptation circuit 106 is basically the dynamic compression circuit 10
7, but in this case very slight but very accurate frequency effects are required. The signal to be transmitted is transmitted via an amplitude modulated transmitter 108 with an output circuit 109 to a tuned implanted receiver circuit 110 and a demodulator 111 and from there to an electrode 112.

The circuit used for dynamic compression, shown in FIG. The output parts of these differential amplifiers are connected in parallel with each other. Point 122.123
The output voltage obtained as the difference voltage between (y, y) is
It depends logarithmically on the input voltage at point 121. This input voltage is led via a capacitor 113 to a point 124 at the input of the integrated circuit 112 to suppress any DC voltage that may be present. Resistor 120 is connected to point 124 of circuit 112.
used to fix the DC voltage level of point 12
The differential voltage between 2.123 and 123
Arithmetic amplifier 11 forming a subtraction circuit together with 15 to 118
4, it can be changed to an unbalanced voltage. Trimmer potentiometer 119 is used to balance the offset voltage.

FIG. 12 shows a circuit diagram of an amplitude modulation oscillator. The transmitter is
It includes an oscillator 120 producing a carrier frequency of 12 MHz and an output stage. The output circuit 126 forms a bandpass filter with an implanted receiver circuit 127 tuned to the same frequency. Current-controlled (and therefore high input ohmic resistance) bandpass filters exhibit a maximum value of the secondary induced voltage at a given coupling, the so-called critical coupling. Therefore, around this fixed point, the secondary induced voltage hardly depends on the coupling. Accordingly, with the inductive coupling used in this case, the tolerance characteristics regarding the positional movement of the transmitting coil are very loose at the distance between the transmitting coil and the receiving coil that causes critical coupling. The critical distance is kept at 10-12 m by choosing the quality of the circuit appropriately. When the transmitter coil diameter is 23mm and the movement is ±101mm, the amount of variation in the secondary voltage is only 15%.

Due to the high quality of the circuit required for the oscillator circuit,
Since saturation of the output run sister 128 must be avoided, collector modulation cannot be used for amplitude modulation, but must rely on emitter current modulation or (as in the illustrated example) base modulation. The modulation voltage is the resistor 133
, a coupling coil 134 and a resistor 130 to the base.

The resistor 130 is selected according to the required output size,
Coupling coil 13 enables accurate value of high frequency control output
The troublesome change of the number of turns of 4 becomes unnecessary.

Capacitors 131 and 132 are used for coupling the modulation input and operating voltage supply to ground according to high frequencies. Schottky diode 127 prevents the occurrence of instability that would cause oscillations in the event of unexpected saturation of the output run sister.

The transmitter output circuit 126 is located on the Plexiglas earpiece so that it can be precisely positioned via the implanted receiver coil.

The entire transmitter is small and can also be mounted on an ear piece. In this case, the total length of the high frequency circuit is 2cI11 or less, and since it hardly acts as an antenna, there is an advantage that radiation of electromagnetic waves is small.

The above-described method of electrically stimulating hearing using the multi-frequency device of the invention improves the hearing of deaf and hard of hearing individuals.

By dividing the audible signal into bands and selectively stimulating various locations within the whorl, the quality and intelligibility of the auditory sensation is improved. Since the implanted receiver circuit consists only of passive electronic elements, no power supply is required and only the stimulation signal needs to be transmitted through the skin and into the body.

A hearing prosthesis comprising the cochlear multichannel electrode of the present invention is easy to manufacture, and the manufacturing method described above provides precise positioning of the electrode contacts to obtain the desired pitch window during the stimulation of the whorl. . Although pulse width modulation is used in the example described above, other modulations may be used, such as amplitude modulation or frequency modulation.

The analog stimulation signal may be used like a pulsed signal or a digital signal after appropriate electronic processing. In the example using the digital signal mentioned above, the audible frequency band is 40 to 40.
0 Hz, which may have the same frequency range as the audio frequency band, not only in digital circuits but also in analog circuits.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a human ear showing the arrangement of the auditory electrical stimulation device using the multi-channel electrode device of the present invention;
Figure 3 is an electrical block diagram illustrating a preferred embodiment of an external sound processing and transmitting device as part of a multi-frequency device for enhancing electrical stimulation of the ear; FIG. 4 is an electrical block diagram illustrating a multi-channel receiver as part of a multi-frequency device for the multi-channel receiver; FIG. Figure 6 is a perspective view of a multi-channel electrode device for circular implantation of the present invention used as part of an electrical stimulation device for auditory sensation, and Figure 6 is a schematic diagram of the human ear to show pitch specificity. The frequency (Hz) that causes maximum activity in the auditory nerve at a given point along
), FIG. 7 is a schematic sectional view of the multichannel electrode device for cochlear implantation according to the present invention shown in FIG.
The figure is a perspective view showing a mold for manufacturing the multi-channel electrode device of the present invention shown in FIG. 7, FIG. Figure 9a is an explanatory diagram showing the inserted state of the multi-channel electrode device, Figure 10 is an electrical block diagram showing the external acoustic processing transmitter, and Figure 11 is an electrical diagram of the dynamic range compression circuit shown in Figure 10. Wiring diagram: FIG. 12 is an electrical wiring diagram showing a preferred embodiment of the transmitting device shown in FIG. 1θ. In the figure, 10 is the external ear, 12 is the eardrum, 14 is the auditory ossicles,
16 is the width, 22 is the annular tube, 24 is the auditory nerve, 30 is the transmitter, 32, 34, 36.38 is the coil, 42.43 is the conducting wire, 46 is the electrode, 5o is the bandpass filter, 52 is the microphone, 54 is an amplifier, 58 is a comparator, 60 is a frequency-voltage converter, 62 is a voltage-frequency converter, 66 is a rectifier, 68
is a logarithmic amplifier, 76.78 is a transmitter coil, 81, 82
゜83.84 is the coil, 90.100 is the electrode body, 91
is a conductor, 92 is an electrode contact, and 93.94 is a conductor.

Claims (3)

[Claims] (1) A slender, tissue-compatible molded body is provided, a plurality of conductive wires are arranged inside the molded body, each of the plurality of conductive wires terminates in one electrode contact, and each electrode contact is connected to the molded body, respectively. A multichannel electrode device for cochlear implantation, wherein each conductor is corrugated to make the electrode flexible and free from tensile loads. (2) A multichannel electrode device according to claim 1, wherein each of the electrode contacts is positioned on the surface of the molded body so that the cochlea can be stimulated in accordance with its frequency assignment. (3) manufacturing a multichannel electrode device comprising an elongated tissue-compatible molded body having a plurality of conductive wires disposed therein, each terminating in an electrode contact, and having each of the plurality of electrode contacts attached to the surface thereof; A method comprising: (a) preparing a plurality of conductive wires each having one contact at the tip; (b) corrugating each of the conductive wires to increase the flexibility of the electrode body; and (c) corrugating each of the conductive wires. A method for manufacturing a multichannel electrode device, characterized in that: (d) filling the mold with a tissue-compatible material; and (d) filling the mold with a tissue-compatible material. .