JP6857882B2 - How to operate the implantable laryngeal electrical stimulator and how to evaluate it - Google Patents

Description

The present invention relates to a method of operating an implantable laryngeal electrical stimulator and a method of evaluating the method.

Vocal cord movement is regulated by the contraction of a small muscle called the internal laryngeal muscle. This muscle contraction is controlled by a very thin nerve called the recurrent laryngeal nerve. When this nerve is damaged by surgery or illness, the vocal cords become immobile and various dysfunctions may occur. For example, one vocal cord may become unable to adduction due to paralysis. In this case, even if the unparalyzed vocal cords are inverted, the glottis is not completely closed, which may lead to voice disorder and dysphagia. For such disorders, surgical treatment has been performed to move and fix the paralyzed vocal cords inward. This causes the glottis to close when the unparalyzed vocal cords adduction.

Meanwhile, research and clinical application of laryngeal pacing that directly stimulates the paralyzed vocal cord muscles using electrodes connected to an implantable stimulus generator is also underway. Conventional laryngeal pacing is primarily aimed at reducing dyspnea due to bilateral vocal cord paralysis by inducing vocal cord dilatation and eliminating the need for tracheostomy. The system described in Patent Document 1 is an example of a system used for such laryngeal pacing.

Japanese Unexamined Patent Publication No. 2004-524125

The results of the above surgical treatments are not bad at all. However, this surgery fixes the paralyzed vocal cords in an inverted state and does not restore the mobility of the vocal cords. In addition, the surgical results inevitably depend on the skill of the surgeon. Therefore, the present inventor reduces the disorder by inducing a closing movement in the vocal cords by using electrical stimulation, as in the case of unilateral vocal cord paralysis and bilateral vocal cord paralysis. I thought about it.

However, as described above, the main purpose of laryngeal pacing so far is to reduce dyspnea due to bilateral vocal cord paralysis by inducing dilatation of the vocal cords by electrical stimulation. Therefore, the electrodes used for electrical stimulation are specialized for stimulating the open muscles of the vocal cords. Since the vocal cord obturator muscle is significantly different in shape from the vocal cord obturator muscle, the electrodes used in conventional laryngeal pacing are not suitable for stimulating the vocal cord obturator muscle due to their shape and function.

An object of the present invention is to provide a method for operating an implantable laryngeal electrical stimulator suitable for applying electrical stimulation to the closed muscles of the vocal cords and a method for evaluating the operation method.

The method of operating the implantable laryngeal electrical stimulator of the present invention has one or more first electrodes, is elongated in one direction, and can spread along the gap between the thyroid fissure muscle and the thyroid cartilage. in, and an electrode unit formed so as to be able to extend in an elongated towards the rear from the front of the gap, and a second electrode, at least one selected from the one or more first electrode wherein a power supply unit for generating a current between the first electrode and the second electrode, and wherein at least certain said first electrode is either the one or more first electrodes of, An electrode for electrical stimulation of the thyroid fissure muscle to a portion posterior to the center in the anterior-posterior direction, and an implantable laryngeal electrical stimulation device arranged at a position on the end side of the center in the electrode unit in the one direction. a method of operation, Ru to generate current for the prescribed first electrode. The "anterior portion of the gap" is, for example, a portion of the gap near the midline of the thyroid cartilage. Further, the "posterior portion of the gap" is, for example, a portion near the arytenoid cartilage portion in the gap.

According to the method of operating the implantable laryngeal electrical stimulator of the present invention, the electrode unit is elongated in one direction, and at least one of the first electrodes is arranged on the end side thereof. Therefore, when the electrode unit is arranged so as to extend from the anterior portion to the posterior portion of the gap between the thyroarytenoid muscle and the thyroid cartilage, the first electrode on the end side is likely to be arranged at the rear portion of the gap. Therefore, the first electrode (predetermined first electrode) on the end side is appropriately arranged at a position close to the arytenoid cartilage of the thyroarytenoid muscle, that is, a position behind the center where electrical stimulation can be applied. .. The portion of the thyroarytenoid muscle close to the arytenoid cartilage corresponds to a portion where muscle contraction using electrical stimulation can be easily controlled, as shown in an experiment described later. Therefore, by using the first electrode on the end side, it is easy to control the reaction of the thyroarytenoid muscle by electrical stimulation. As described above, according to the present invention, a method of operating a device suitable for applying electrical stimulation to the thyroarytenoid muscle, which is the obturator muscle of the vocal cords, is realized.

Further, in the present invention, it is preferable that the electrode unit has a plurality of the first electrodes having different positions on the electrode unit in the one direction. According to this, a plurality of first electrodes having different positions on the electrode unit in one direction, that is, in the long direction are provided. Therefore, the position where the electrical stimulation is applied to the thyroarytenoid muscle can be variously selected with respect to the longitudinal direction of the electrode unit.

Further, in the present invention, it is preferable that the electrode unit has a plurality of the first electrodes having different positions on the electrode unit in a direction orthogonal to the one direction. According to this, a plurality of first electrodes having different positions in a direction orthogonal to one direction on the electrode unit, that is, a width direction are provided. Therefore, the position where the electrical stimulation is applied to the thyroarytenoid muscle can be variously selected with respect to the width direction of the electrode unit.

In the present invention, the power supply unit, pre SL has a power receiving coil for implantation within the body which are electrode units electrically connected, and a power transmission coil which faces the power receiving coil in vitro, of the power transmission coil It is preferable to generate an induced electromotive force in the power receiving coil by changing the magnitude of the current. According to this, a power supply source such as a battery can be provided outside the body.

Further, in the present invention, it is preferable that the second electrode is provided on the electrode unit. According to this, the thyroarytenoid muscle can be electrically stimulated by the electric current generated between the electrodes on the electrode unit.

Further, the evaluation method of the implantable laryngeal electrical stimulator according to another aspect of the present invention has a plurality of first electrodes, is elongated in one direction, and extends along the gap between the thyroid fissure muscle and the thyroid cartilage. An electrode unit formed so as to be capable of extending from the front portion to the rear portion of the gap, a second electrode, and at least selected from the plurality of first electrodes. A feeding unit for generating a current between the first electrode and the second electrode is provided, and at least one of the plurality of first electrodes is from the center of the thyroid fissure muscle in the anteroposterior direction. an electrode for electric stimulation to the rear portion, a method of assessing the implantable laryngeal electrostimulation device which is disposed at a position of the end portion side from the center with respect to the one direction in the electrode unit, the plurality The functionality of the first electrode is evaluated based on a numerical value or a graph showing the relationship between the magnitude of the current generated for each of the first electrodes of the above and the amount of displacement of the voice band caused by the generation of the current. It has a higher evaluation engineering for.

According to the evaluation method of the implantable laryngeal electrical stimulator of the present invention, the functionality of the first electrode is evaluated according to the change in the displacement amount of the vocal cords with respect to the magnitude of the electric current. Therefore, it is easy to select the first electrode according to the application.

Further, in the present invention, in the evaluation step, it is possible to compare between the first electrodes whether or not the rate of change of the displacement amount with respect to the magnitude of the current is likely to change with respect to the magnitude of the current. preferable. According to this, whether or not the rate of change of the displacement amount is likely to change with respect to the magnitude of the current is compared between the first electrodes. As a result, for example, when the first electrode whose rate of change is unlikely to change is selected, electrical stimulation is applied to the thyroarytenoid muscle so that the displacement amount of the vocal cords shows a reaction close to linear with respect to the magnitude of the current. Can be done. Therefore, it is easy to control the displacement amount of the vocal cords according to the current.

It is a conceptual diagram which shows the structure of the laryngeal electric stimulator which concerns on one Embodiment of this invention. It is a top view of the electrode unit provided in the larynx electrical stimulator of FIG. It is a top view of the indifferent electrode provided in the larynx electrical stimulator of FIG. It is a side view of the larynx. FIG. 5 is a sectional view taken along line VV of FIG. It is a figure which shows the image of the vocal cord by the endoscope inserted from the mouth. It is a flow chart which shows the series flow of the method of evaluating the electrode provided in the electrode unit of FIG. It is a graph which shows the measurement result in the experiment carried out in relation to the evaluation method of FIG.

The laryngeal electrical stimulator 1 (implantable laryngeal electrical stimulator) according to an embodiment of the present invention will be described with reference to the drawings. The laryngeal electrical stimulator 1 is a device for reducing various functional disorders such as voice disorder and dysphagia associated with unilateral paralysis of the vocal cords by applying electrical stimulation to the muscles in the larynx. As shown in FIG. 1, the laryngeal electrical stimulator 1 includes a pulse generator 10, an electrode unit 20, an indifferent electrode 30, a power receiving coil 41, a power transmission coil 42, a battery 43, and a remote controller 50.

The electrode unit 20 is implanted in the human larynx and gives electrical stimulation to the muscles in the larynx, specifically the thyroarytenoid muscle. As shown in FIG. 2, the electrode unit 20 has a substrate 21 and electrodes 22A to 22F. The substrate 21 is a thin flat plate made of silicon resin having a rectangular outer edge. The size of the substrate 21 is, for example, 8 mm × 12 mm. Hereinafter, the direction along the substrate 21 (direction orthogonal to the thickness direction of the substrate 21) and along the long side of the rectangle is referred to as a long direction (one direction). Further, the width direction is a direction along the substrate 21 and orthogonal to the long direction. The electrodes 22A to 22F are electrodes that apply electrical stimulation to the thyroarytenoid muscle. The electrodes 22A to 22F are provided on the substrate 21. Of these, the electrodes 22C and 22F are arranged along the width direction on the end portion 21a side of the center L1 of the substrate 21 in the longitudinal direction. The term "end 21a side from the center L1" means that the distance to the end 21a is smaller than the distance between the center L1 and the end 21a, and the same applies hereinafter. The electrodes 22B and 22E are aligned along the width direction at the center L1 of the substrate 21 in the longitudinal direction. The electrodes 22A and 22D are arranged along the width direction on the end portion 21b side of the center L1 of the substrate 21 in the longitudinal direction. In this way, the six electrodes 22A to 22F are arranged in a grid dot pattern on the substrate 21 in a three-row, two-column arrangement in which three are arranged along the longitudinal direction and two are arranged along the width direction. ing. The electrode unit 20 is connected to the pulse generator 10 via a cable 23. The cable 23 is connected to the end 21b. The cable 23 includes six signal lines 23a. Each signal line 23a is connected to each of the electrodes 22A to 22F.

As shown in FIG. 3, the unrelated electrode 30 paired with the related electrodes 22A to 22F is provided at the tip end portion 31a of the cable 31. The cable 31 is connected to the pulse generator 10. The cable 31 includes wiring 31b. The wiring 31b is connected to the indifferent electrode 30. The irrelevant electrode 30 is installed at a position (for example, directly below the clavicle) away from the electrode unit 20 in the human body.

The power receiving coil 41 is embedded in a place (for example, the chest) away from the electrode unit 20 in the human body. As shown in FIG. 1, the power receiving coil 41 is electrically connected to the pulse generator 10. The power transmission coil 42 paired with the power receiving coil 41 is electrically connected to the battery 43. The battery 43 supplies an alternating current (or a fluctuating current) to the power transmission coil 42. The battery 43 is provided with a switch for switching on / off of the current supply to the power transmission coil 42. When the switch of the battery 43 is switched on while the power transmission coil 42 is arranged at a position facing the power reception coil 41 outside the body, an alternating current is generated in the power transmission coil 42. When an alternating current is generated in the power transmission coil 42, an induced electromotive force is generated in the power receiving coil 41 due to a change in the electric field.

The pulse generator 10 receives electric power by the induced electromotive force generated in the power receiving coil 41. The pulse generator 10 uses the electric power supplied from the power receiving coil 41 to pass through the wiring 23a of the cable 23 and the wiring 31b of the cable 31 between the electrodes 22A to 22F on the current unit 20 and the unrelated electrode 30. Generate a pulse current. The pulse current is continuously supplied between the electrodes at predetermined time intervals. In this pulse current, the shape of the pulse is rectangular. The pulse generator 10 selects any one of the six electrodes 22A to 22F and generates a current between the selected electrode and the unrelated electrode 30. Further, the pulse generator 10 can select any two of the six electrodes 22A to 22F and generate a current between the two electrodes. When a current is generated between any of the electrodes 22A to 22F and the unrelated electrode 30, any of the electrodes 22A to 22F is used as the first electrode of the present invention, and the unrelated electrode 30 is used as the second electrode of the present invention. Corresponds to each. When a current is generated between any two of the electrodes 22A to 22F, one electrode corresponds to the first electrode of the present invention and the other electrode corresponds to the second electrode of the present invention. The pulse generator 10 can continuously generate a pulse current between the electrodes while changing the strength (amplitude) of the pulse current, the pulse width, and the interval (frequency) between the pulses. Further, the pulse generator 10 includes a receiving unit that wirelessly receives a control signal from the remote controller 50. The pulse generator 10 operates according to a control signal from the remote controller 50.

The remote controller 50 is a switch that switches the pulse current on and off, a switch that selects the electrodes that supply the pulse current from the six electrodes 22A to 22F, the strength (amplitude) of the pulse current, the pulse width, and the pulses. It is equipped with a switch that changes the interval (frequency) of. The remote controller 50 includes a transmission unit that wirelessly transmits a control signal according to the content instructed by these switches to the pulse generator 10. When the control signal is transmitted from the remote controller 50 to the pulse generator 10, the pulse generator 10 continuously generates a pulse current between the electrodes at predetermined time intervals according to the content indicated by the control signal. For example, the frequency of a square wave composed of such continuous rectangular pulse currents may be 40 to 50 Hz, the pulse width may be 0.5 to 1 ms, and the pulse current strength may be 5 mA or less.

Hereinafter, the installation mode and function of the electrode unit 20 will be described in more detail. In the following description, each direction of front, back, left, right, up and down is based on the person in which the electrode unit 20 is embedded. The electrode unit 20 is installed in the human larynx as shown in FIGS. 4 and 5. Specifically, the electrode unit 20 is inserted into the gap S between the thyroarytenoid muscle and the thyroid cartilage, which is one of the pair of left and right thyroarytenoid muscles in which unilateral paralysis has occurred. As shown in FIG. 5, the thyroid cartilage has a portion extending diagonally backward to the left from the anterior part of the larynx and a portion extending diagonally posteriorly to the right from the anterior part of the larynx, and is viewed from above. It has a V shape. The pair of left and right thyroarytenoid muscles are both inside the thyroid cartilage. When viewed from the left side of the larynx, the thyroarytenoid muscle on the left side extends in a fan shape from the vicinity of the anterior part of the thyroid cartilage toward the diagonally posterior left side as shown in FIG. The thyroarytenoid muscle on the right side extends in a fan shape from the vicinity of the anterior part of the thyroid cartilage to the diagonally posterior right side when viewed from the right side of the larynx. The recurrent laryngeal nerve extends from below toward this thyroarytenoid muscle.

The gap S between the thyroarytenoid muscle and the thyroid cartilage extends obliquely posterior to the left or diagonally posterior to the right from the vicinity of the anterior portion of the thyroid cartilage. The electrode unit 20 is inserted into the gap S through a fenestration G preformed in the anterior portion of the thyroid cartilage. The size of the window opening G is, for example, 8 mm × 12 mm. Then, as shown in FIGS. 4 and 5, the electrode unit 20 extends along (a) the gap S, (b) extends from the front Sf of the gap S toward the rear Sr, and (c). ) It is placed so as to straddle the terminal part of the recurrent laryngeal nerve located in the thyroarytenoid muscle in the anterior-posterior direction. As a result, as shown in FIG. 4, the electrode unit 20 is arranged at a position where the electrodes 22C and 22F on the end 21a side overlap with the portion of the thyroarytenoid muscle posterior to the central C1 (the portion close to the arytenoid cartilage). , The electrodes 22A and 22D on the end 21b side are arranged at positions overlapping the portion of the thyroarytenoid muscle in front of the central C1. Therefore, the electrodes 22C and 22F apply electrical stimulation to the portion of the thyroarytenoid muscle posterior to the central C1. Electrodes 22A and 22D apply electrical stimulation to the portion of the thyroarytenoid muscle anterior to central C1. The anterior portion Sf in the above (a) is a portion in the gap S near the midline of the thyroid cartilage. The posterior Sr is a portion in the gap S near the arytenoid cartilage portion.

By operating the remote controller 50 with the electrode unit 20 inserted as described above, electrical stimulation by a pulse current from any of the electrodes 22A to 22F can be applied to the thyroarytenoid muscle. When an electrical stimulus is applied to the thyroarytenoid muscle, the vocal cord V1 on the side to which the electrical stimulus is applied out of the pair of left and right vocal cords inverts in the direction of the arrow Aw in FIG. In the following, the degree of adduction of vocal cord V1 is shown by the angle θ between the median line Q and the vocal cord free edge P (see FIG. 6). The amount of change in θ corresponds to the amount of displacement of the vocal cords. When θ takes a positive value, it indicates that the vocal cords are in the state shown in FIG. 6 in which the glottis is opened. When θ is zero, it means that the vocal cords are inverted from the state shown in FIG. 6 and the vocal cord free edge P is located at the midline. When θ takes a negative value, it indicates that the vocal cords are further inverted and the vocal cord free edge P is in a state of crossing the median plane.

By the way, when applying electrical stimulation to the thyroarytenoid muscle using the laryngeal electrical stimulator 1 as described above, electrical stimulation in the thyroarytenoid muscle is applied depending on which of the electrodes 22A to 22F is used to apply the electrical stimulation. The position changes. The thyroarytenoid muscle responds differently to electrical stimulation depending on its position. Therefore, it is important to evaluate which of the electrodes 22A to 22F is suitable for imparting electrical stimulation to the thyroarytenoid muscle according to the reaction mode of the thyroarytenoid muscle. Hereinafter, an evaluation method (evaluation method for an implantable laryngeal electrical stimulator) for evaluating which of the electrodes 22A to 22F is suitable for applying electrical stimulation to the thyroarytenoid muscle will be described with reference to FIG. 7.

First, the electrode unit 20 is installed in the gap S between the thyroarytenoid muscle and the thyroid cartilage on the vocal cord side where unilateral paralysis has occurred (S1). At this time, the electrode unit 20 is installed in the gap S so as to satisfy the above (a) to (c). Next, using the remote controller 50, one of the electrodes 22A to 22F is selected to apply electrical stimulation to the thyroarytenoid muscle (S2). Then, the degree to which the vocal cords adduction when an electrical stimulus is applied to the thyroarytenoid muscle is measured (S3). This measurement is performed by photographing the vocal cords through an endoscope inserted through the mouth of the subject and then acquiring the angle θ shown in FIG. 6 from the imaging results. In this way, in the steps (S2 and S3) of applying electrical stimulation to the thyroarytenoid muscle to measure the degree of vocal cord adduction, while changing the strength of the pulse current supplied to the electrodes, the electrodes 22A to 22A to Repeat while changing the electrode to be used from 22F. Then, based on the result of repeatedly executing S2 and S3 in this way, which of the electrodes 22A to 22F is suitable for imparting electrical stimulation (electrode functionality) is evaluated (S4).

The present inventor conducted the following experiments in relation to the evaluation method. The recurrent laryngeal nerve of the dog was cut once and anastomosed immediately, and then a fenestration (through hole) was formed in the anterior part of the thyroid cartilage of the dog (the part corresponding to the bidotal chain line G in FIG. 4). Next, the electrode unit 20 was inserted and fixed in the gap between the thyroarytenoid muscle and the thyroid cartilage so as to satisfy the above (a) to (c). The electrode unit 20 has a size of 8 mm × 12 mm. Then, for each of the electrodes 22A to 22F of the electrode unit 20, a rectangular pulse current is applied for a predetermined time while changing the magnitude of the current (strength of the pulse current) by 0.5 mA in the range of 0 to 2.5 mA. Supplied continuously at intervals. The frequency of the square wave composed of the continuous rectangular pulse current was 40 Hz, and the pulse width was 1 ms. In addition, a CCD (Charge Coupled Device) was inserted into the mouth of the dog, and the reaction of the vocal cords to the application of electrical stimulation by the electrode unit 20 was photographed. Then, the angle θ was acquired from the image of the image captured by the CCD. The reason why this experiment was conducted on dogs is that the size and shape of the larynx of dogs are similar to those of humans, and that dogs use voice for communication like humans.

The graph of FIG. 8 shows the change of the angle θ (degree; degree) acquired in this experiment with respect to the strength of the pulse current for each of the electrodes 22A to 22D and 22F. In this experiment, data could not be obtained well for the electrode 22E. As shown in FIG. 8, for the electrodes 22A, 22B and 22D, when the pulse current was increased in the range of 0 to 1.0 mA, the degree of vocal cord adduction increased sharply. On the other hand, when the current exceeds 1.0 mA, the degree of vocal cord adduction is less likely to change. On the other hand, for the electrodes 22C and 22F, the degree of vocal cord adduction gradually increased as the pulse current was increased over the entire range of 0 to 2.5 mA.

Based on the experimental results shown in FIG. 8, for the electrodes 22A, 22B and 22D, the change in the vocal cords is too rapid with respect to the change in the strength of the pulse current as compared with the electrodes 22C and 22F. Therefore, in order to control the adduction of the vocal cords by adjusting the current value, it can be seen that it is easier to control using the electrodes 22C and 22F than using the electrodes 22A, 22B and 22D. Therefore, in the evaluation of the electrodes, the electrodes 22C and 22F are more suitable for applying electrical stimulation to the thyroarytenoid muscle than the electrodes 22A, 22B and 22D. Further, as described above, the electrodes 22C and 22F apply electrical stimulation to the portion of the thyroarytenoid muscle posterior to the central C1 (the portion close to the arytenoid cartilage). From this, the part posterior to the central C1 in the thyroarytenoid muscle is the part in which the reaction gradually increases as compared with the part anterior to the central C1 in the thyroarytenoid muscle when the electrical stimulation is strengthened. It can be seen that it is a part where it is easy to control muscle contraction using stimulation.

As described above, in the present embodiment, as an evaluation method of the laryngeal electrical stimulator 1, whether or not the degree of vocal cord adduction suddenly changes with respect to the magnitude of the current (strength of the pulse current) is determined. The electrodes 22A to 22F are compared with each other. Then, it is evaluated that the electrode in which the degree of adduction of the vocal cords does not change rapidly with respect to the magnitude of the current is more suitable for applying electrical stimulation than the other electrodes. In this evaluation standard, the degree of vocal cord adduction changes (or does not) rapidly with respect to the magnitude of the current, so that the rate of change of the angle θ with respect to the magnitude of the current tends to change with respect to the magnitude of the current. It may be rephrased as (difficult). In the above experimental results, the amount of change in the angle θ (difference between adjacent measured values θ in the graph of FIG. 8) when the strength of the pulse current is increased by 0.5 mA may be used as the rate of change in the angle θ. Then, by acquiring the maximum value of the absolute value of the rate of change for each electrode and comparing the maximum value between the electrodes, it is possible to determine whether or not the rate of change of the angle θ is likely to change with respect to the magnitude of the current. You may compare. Further, an approximate curve representing a change in the angle θ with respect to the magnitude of the current is acquired based on the measured value of θ, and whether or not the absolute value of the second-order differential coefficient of the angle θ with respect to the current in the approximate curve is equal to or less than a predetermined value. Based on the above, it may be evaluated whether or not the rate of change of the angle θ with respect to the magnitude of the current is likely to change with respect to the magnitude of the current. It can be evaluated that the closer the absolute value of the second-order differential coefficient of the approximate curve is to zero, that is, the closer the mode of change of θ with respect to the current is to linear, the more suitable the electrode is for applying electrical stimulation. As shown in FIG. 8, when it is clear from the comparison of the graphs of the electrodes whether or not θ is likely to change rapidly with respect to the change in current, whether or not it is suitable for applying electrical stimulation. May be evaluated based on a comparison of graphs.

According to the laryngeal electrical stimulator 1 of the present embodiment described above, the electrode unit 20 is long in one direction. Then, the electrode unit 20 is arranged so as to extend long from the portion near the midline of the thyroid cartilage (anterior portion) to the portion near the arytenoid cartilage (rear portion) in the gap S between the thyroarytenoid muscle and the thyroid cartilage. .. As a result, the electrodes 22C and 22F on the end 21a side are arranged on the back side (rear side) of the gap S, and electrical stimulation is applied to the portion of the thyroarytenoid muscle behind the central C1. The portion of the thyroarytenoid muscle close to the arytenoid cartilage corresponds to the portion where muscle contraction using electrical stimulation is easily controlled, as shown in the above experiment. Therefore, when the electrodes 22C or 22F are used, it is easy to control the reaction of the thyroarytenoid muscle by electrical stimulation. As described above, the laryngeal electrical stimulator 1 is suitable for applying electrical stimulation to the thyroarytenoid muscle, which is the obturator muscle of the vocal cords.

Further, in the present embodiment, in the electrode unit 20, three electrodes 22A to 22F are arranged in a grid dot pattern in a three-row, two-column arrangement in which three electrodes 22A to 22F are arranged along the longitudinal direction and two are arranged along the width direction. ing. As described above, since a plurality of electrodes are provided at different positions in the elongated direction and the width direction, the positions where the electrical stimulation is applied to the thyroarytenoid muscle are set in the elongated direction and the width direction of the electrode unit 20, respectively. You can make various choices regarding. From the viewpoint of ease of controlling the reaction of the thyroarytenoid muscle by electrical stimulation, it is preferable to apply electrical stimulation to the inner portion of the thyroarytenoid muscle as described above. On the other hand, depending on individual differences, differences in paralysis mode, etc., it may be better to apply electrical stimulation to a position different from the position corresponding to the electrodes 22C or 22F in order to reduce the damage caused by electrical stimulation. .. According to the electrode unit 20, since various positions for applying electrical stimulation can be selected in each of the long direction and the width direction, it is easy to deal with individual differences and differences in the mode of paralysis. Further, since a plurality of electrodes are provided, even if the function of one of the electrodes deteriorates due to aged deterioration or the like, another electrode can be used instead of the deteriorated electrode to apply electrical stimulation to the thyroarytenoid muscle. ..

<Modification example>
The above is a description of a preferred embodiment of the present invention, but the present invention is not limited to the above-described embodiment, and various changes can be made as long as it is described in the means for solving the problem. It is possible.

For example, in the above-described embodiment, a pulse current is generated between any of the electrodes 22A to 22F on the electrode unit 20 and the unrelated electrode 30. However, a pulse current may be generated between any two of the electrodes 22A to 22F. In the experiment conducted by the present inventor on dogs, pulse currents were generated between the electrodes 22A and 22D, between the electrodes 22B and 22E, and between the electrodes 22C and 22F. In both cases, the vocal cords were properly inverted.

Further, in the above-described embodiment, six electrodes including the electrodes 22C and 22F on the end portion 21a side are provided on the electrode unit 20. However, it is also within the scope of the present invention that only one of the electrodes 22C and 22F is provided on the end portion 21a side of the substrate 21 and no other electrodes are provided. Even in such a configuration, since the electrode is provided on the end portion 21a side of the long substrate 21, when the substrate 21 is placed in the gap between the thyroarytenoid muscle and the thyroid cartilage, electrical stimulation is applied to the thyroarytenoid muscle. It is easy for the electrodes to be placed at positions that can be applied to the inner part of the. Therefore, the configuration is suitable for applying electrical stimulation to the thyroarytenoid muscle.

10 Pulse generator 20 Electrode unit 22A-22F Electrode (Seki electrode)
30 Indifferent electrode 41 Power receiving coil 42 Power transmission coil 43 Battery

Claims (7)

It has one or more first electrodes, is elongated in one direction, can spread along the gap between the thyroarytenoid muscle and the thyroid cartilage, and from the front to the back of the gap. An electrode unit formed so that it can be extended to a long length,
With the second electrode
A power supply unit for generating a current between at least one of the first electrode and the second electrode selected from the one or more first electrodes,
Is equipped with
The predetermined first electrode, which is at least one of the one or more first electrodes , is an electrode for electrical stimulation to a portion of the thyroarytenoid muscle behind the center in the anterior-posterior direction, and is the electrode unit. It is a method of operating an implantable laryngeal electrical stimulator located at a position closer to the end than the center in one direction.
Method for operating an implantable laryngeal electrostimulation device according to claim Rukoto to generate current for the prescribed first electrode. The method for operating an implantable laryngeal electrical stimulator according to claim 1, wherein the electrode unit has a plurality of the first electrodes having different positions on the electrode unit in one direction. The implantable laryngeal electricity according to claim 1 or 2, wherein the electrode unit has a plurality of the first electrodes having different positions on the electrode unit in a direction orthogonal to the one direction. How to operate the stimulator. The power feeding unit has a power receiving coil for implantation in the body that is electrically connected to the electrode unit and a power transmitting coil that faces the power receiving coil outside the body, and changes the magnitude of the current of the power transmitting coil. The method for operating an implantable throat electrical stimulator according to any one of claims 1 to 3, wherein an induced electromotive force is generated in the power receiving coil. The method for operating an implantable laryngeal electrical stimulator according to any one of claims 1 to 4, wherein the second electrode is provided on the electrode unit. It has a plurality of first electrodes, is long in one direction, is long so that it can spread along the gap between the thyroarytenoid muscle and the thyroid cartilage, and is long from the front part to the rear part of the gap. An electrode unit formed so that it can be extended to
With the second electrode
A power feeding unit that generates a current between at least one of the first electrodes selected from the plurality of first electrodes and the second electrode.
Is equipped with
At least one of the plurality of first electrodes is an electrode for electrical stimulation to a portion of the thyroarytenoid muscle behind the center in the anterior-posterior direction, and the position of the electrode unit on the end side of the center in the one direction. a method of evaluating an implantable laryngeal electrostimulation device which is arranged,
The functionality of the first electrode is based on a numerical value or a graph showing the relationship between the magnitude of the current generated for each of the plurality of first electrodes and the displacement amount of the vocal cords caused by the generation of the current. evaluation method of implantable laryngeal electrostimulation apparatus characterized by comprising a higher evaluation Engineering to evaluate. The sixth aspect of the invention is characterized in that, in the evaluation step, whether or not the rate of change of the displacement amount with respect to the magnitude of the current is likely to change with respect to the magnitude of the current is compared between the first electrodes. The method for evaluating an implantable laryngeal electrical stimulator described.

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