JP2012045103A - Electrical stimulator device and electrode lead - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrical stimulator device and an electrode lead by which insertion of the electrode lead, fixation thereof in a prescribed position in a body, and extraction from the inside of the body can be easily carried out.SOLUTION: The indwelling electrical stimulator device includes a flexible electrode lead made of a long body, and a stimulator device that generates a stimulator signal that is supplied to the electrode lead. The electrode lead further includes: an intraluminal insertion part, having an indwelling stimulator electrode that stimulates neurons and/or muscle; and a winding part, disposed nearer the base end than the intraluminal insertion part. The stimulator device further includes a stimulator circuit that is electrically connected to the stimulator electrode, and that applies the stimulator signal to the stimulator electrode.

Description

  The present invention relates to an electrical stimulation device that electrically stimulates a living body and an electrode lead constituting the electrical stimulation device, and more particularly to an electrical stimulation device and an electrode lead that are used by being completely implanted in a living body.

  At present, pain is alleviated by electrical stimulation of nerves when it is not effective in conventional drug therapy, nerve block therapy or surgical therapy, or when the treatment cannot be continued due to side effects. Electrical stimulation therapy is effective. Spinal cord electrical stimulation therapy, which is one type of electrical stimulation therapy, is a stimulation therapy that electrically stimulates the spinal cord in order to relieve pain transmitted to the brain through the spinal cord.

  In spinal cord electrical stimulation therapy, a trial period of 24 hours to several weeks is usually provided in order to confirm the effectiveness of pain relief by electrical stimulation. In the trial period, a stimulation electrode is generally placed in the epidural space outside the spinal dura covering the spinal cord by puncturing from the back side, and then the electrode lead including the stimulation electrode is connected to an external stimulation device. Connect to examine pain relief under various stimulation patterns. During this period, the electrical stimulation device is not implanted. Only when a predetermined effect is recognized during the trial period, the electrical stimulation device is implanted (hereinafter referred to as “main implantation”).

  When the electrostimulator is to be implanted, after the electrode lead placed in the trial period is removed, a new stimulation electrode is placed again in the epidural space, and the electrode lead containing the stimulation electrode is subcutaneously placed. It is led to the waist, abdomen, or chest through the tunnel. Then, the electrode lead is connected to the electrical stimulation device and implanted subcutaneously.

  By the way, during the trial period or after the main implantation, there is a problem that the electrode lead is pulled along with the movement of the patient's body, and the position of the stimulation electrode deviates from the initial implantation position. If the position of the stimulation electrode is shifted, a sufficient pain relieving effect cannot be obtained, or stimulation is felt at a site unrelated to the pain, thereby causing discomfort such as numbness in the patient. For this reason, the electrode lead has to be implanted again.

  In order to solve this problem, an electrode lead in which a portion arranged in the epidural space, that is, a tip side portion is formed in a spiral shape has been considered. This electrode lead prevents the displacement of the stimulation electrode due to the pulling of the electrode lead by pressing the inner wall of the epidural space with a helically formed part (hereinafter referred to as “spiral structure part”). (See Patent Document 1).

Japanese Patent Publication No. Hei 3-41191

  As described above, the electrode lead described in Patent Document 1 is implanted in a living body so that the helical structure is located in the epidural space. Although the epidural space is sparse, it includes adipose tissue, connective tissue, and blood vessels, and tissues and blood vessels are formed so as to gradually become entangled with the helical structure. Therefore, when removing the electrode lead from the living body, it is necessary not to damage the blood vessel or tissue in the epidural space through which the spiral structure part passes or the blood vessel or tissue entangled with the spiral structure part. The lead removal was a very difficult task.

  In this regard, if a stylet is inserted into the electrode lead to deform the helical structure into a straight line, it can be removed without damaging the blood vessel or tissue. However, since the shape of the helical structure is almost fixed by the epidural space, there is a high possibility that the stylet cannot pass through the helical structure. In addition, the stylet may break through the body of the electrode lead when it is forced to pass through.

  The present invention has been made in view of such points, and an object thereof is to provide an electrical stimulation device and an electrode lead that can be easily inserted into the body, fixed to a predetermined position in the body, and removed from the body.

  In order to solve the above-described problems, an electrical stimulation device of the present invention is provided with an electrode lead made of a flexible elongated body and a stimulation device that generates a stimulation signal to be supplied to the electrode lead, and is placed in a living body. Is an electrical stimulator. The electrode lead includes a lumen insertion portion having a stimulation electrode that stimulates nerves and / or muscles in a living body, and a winding portion that is provided on the proximal side of the lumen insertion portion and has a continuous curved structure. . The stimulation apparatus includes a stimulation circuit that is electrically connected to the stimulation electrode and applies a stimulation signal to the stimulation electrode.

  According to the above-described configuration of the present invention, since the winding portion of the electrode lead is made of a flexible long body, it can be deformed into a substantially linear shape. In this state, the electrode lead is implanted into the living body.

  In addition, since the winding portion is provided on the proximal end side with respect to the lumen insertion portion having the stimulation electrode, the lumen insertion portion is arranged inside the living body lumen and wound outside the living body lumen. The electrode lead can be implanted in the living body in a state where the portion is disposed. In the implanted state, the wound portion is surrounded by the surrounding tissue outside the lumen (hereinafter referred to as “extraluminal surrounding tissue”) and remains in a substantially straight state. The resilience to return to work. As a result, the extraluminal peripheral tissue is compressed by the wound portion.

According to the present invention, when the electrode lead is implanted in the living body, the wound portion can be deformed substantially linearly, so that the electrode lead can be easily implanted into the body. In addition, in a state where the electrode lead is implanted in the living body, the surrounding tissue outside the lumen can be pressed by the wound portion, so that the stimulation electrode of the electrode lead can be fixed at a predetermined position in the living body. Furthermore, in a state where the electrode lead is implanted in the living body, the winding portion can be kept in a substantially straight state, so that the electrode lead can be easily removed from the living body.
Thus, according to the present invention, it is possible to easily insert the electrode lead into the living body, fix the electrode lead to a predetermined position in the living body, and remove the electrode lead from the living body.

It is a perspective view showing the whole electrical stimulation device concerning a first embodiment of the present invention. It is a perspective view which shows the state by which the stylet of the electrical stimulation apparatus which concerns on 1st embodiment of this invention was inserted. It is a block diagram which shows the function of the irritation | stimulation apparatus which concerns on 1st embodiment of this invention. It is explanatory drawing for demonstrating the procedure (the 1) which implants the electrical stimulation apparatus which concerns on 1st embodiment of this invention in the biological body. It is explanatory drawing for demonstrating the procedure (the 2) which implants the electrical stimulation apparatus which concerns on 1st embodiment of this invention in the biological body. It is explanatory drawing for demonstrating the procedure (the 3) which implants the electrical stimulation apparatus which concerns on 1st embodiment of this invention in in vivo. It is explanatory drawing for demonstrating the procedure (the 4) which implants the electrical stimulation apparatus which concerns on 1st embodiment of this invention in the biological body. It is a perspective view which shows the whole electric stimulation apparatus which concerns on 2nd embodiment of this invention. It is a perspective view which shows the state by which the stylet of the electrical stimulation apparatus which concerns on 2nd embodiment of this invention was inserted. It is a perspective view which shows the whole electric stimulation apparatus which concerns on 3rd embodiment of this invention. It is a perspective view which shows the state by which the stylet of the electrode lead which concerns on 3rd embodiment of this invention was inserted. (A) It is a side view of the electrical stimulation apparatus which concerns on the modification of this invention. (B) It is a front view of the electrical stimulation apparatus which concerns on the modification of this invention.

  Embodiments for carrying out the present invention will be described below. The embodiments described below are preferable specific examples of the present invention. Therefore, various technically preferable limitations are attached. However, the scope of the present invention is not limited to these embodiments unless otherwise specified in the following description. For example, the numerical conditions of each parameter given in the following description are only suitable examples, and the dimensions, shapes, and arrangement relationships in the drawings used for the description are also schematic.

The description will be made in the following procedure.
<First embodiment>
1. 1. Mechanical configuration of electrical stimulation device 2. Configuration of stimulation circuit Procedure for implanting electrical stimulation device <second embodiment>
4). Mechanical Configuration of Electrical Stimulator <Third Embodiment>
5). Mechanical configuration of electrical stimulation device <Modification>

<Description of First Embodiment of the Present Invention>
An example of the first embodiment of the present invention (hereinafter referred to as “this example”) will be described with reference to FIGS.
[1. Configuration of electrical stimulation device]
First, the mechanical configuration of the electrical stimulation apparatus according to the first embodiment will be described with reference to FIG.
FIG. 1 is a perspective view showing the entire electrical stimulation device according to the first embodiment of the present invention, and FIG. 2 is a perspective view showing a state where a stylet of the electrical stimulation device shown in FIG. 1 is inserted. is there.

  The electrical stimulation device 101 stimulates spinal nerves and the like in a living body with electrical stimulation signals (hereinafter referred to as “electrical stimulation signals”). The electrical stimulation apparatus 101 is provided with an electrode lead 102 for stimulating nerves and the like, and a stimulation apparatus 103 for supplying an electrical stimulation signal to the electrode lead 102.

The electrode lead 102 will be described.
The electrode lead 102 includes four stimulation electrodes 108 for stimulating nerves and the like, and a body 104 for fixing each stimulation electrode 108 so as to be exposed to the living body when the electrode lead 102 is disposed in the living body. ing. In this example, the number of stimulation electrodes 108 is four, but this is only an example, and the number of stimulation electrodes 108 can be arbitrarily set.

  The body 104 is made of an elongated body 109 formed of a flexible and biocompatible material, for example, a resin material such as silicone or polyurethane in a substantially cylindrical shape. In the long body 109, a substantially cylindrical hole that opens to the proximal end 111 and communicates to the vicinity of the distal end 112 is opened in the axial direction. This hole is a stylet lumen 106. Therefore, the diameter of the stylet lumen 106 needs to be approximately equal to or slightly longer than the diameter of the stylet 120. Moreover, it is preferable that the outer diameter of the elongate body 109 is 1-3 mm.

  A portion formed by spirally forming a predetermined length from the base end 111 of the long body 109 is a winding portion 105, and the winding portion 105 implants the electrical stimulation device 101 in the living body. In this case, it corresponds to a portion disposed in a tissue such as extraluminal muscle, connective tissue, or fat. Each winding radius of the winding part 105 is approximately equal to about 1 to 1.5 cm.

As shown in FIG. 2, the winding portion 105 is deformed from a spiral shape to a substantially linear shape when the stylet 120 is completely inserted into the stylet lumen 106. In this state, the length of the winding part 105 in the axial direction is about 15 cm including an excessive part (a part from the proximal end 111 to the predetermined distance in the winding part 105) for tearing the epidural needle to be described later. It needs to be set longer than that. This is because, when the stimulation electrode 108 is disposed at a predetermined position in the lumen, the wound portion 105 is included in the tissue regardless of the physical characteristics of the patient (the thickness of the tissue between the skin and the lumen). This is because at least a part of (excluding the surplus part) is arranged and at least the surplus part of the winding part 105 protrudes from the skin surface.
The stimulation device 103 is fixed to the surface of the winding portion 105 in the vicinity of the base end 111 thereof. In this example, the part other than the winding part 105 of the body 104 is referred to as a lumen insertion part 110.

  The lumen insertion part 110 is a part where all or part of the electrical stimulation device 101 is placed in a lumen such as an epidural space when the electrical stimulation device 101 is implanted in a living body. Therefore, for example, when the luminal insertion portion 110 is arranged in the epidural space, the axial length of the luminal insertion portion 110 is three vertebral bodies or a length slightly longer than that. Is preferred. In addition, four stimulation electrodes 108 fixed so as to be exposed from the surface of the body 104 are disposed in the lumen insertion portion 110.

  The stimulation electrode 108 is made of a conductive and biocompatible material, for example, a material such as platinum or a platinum alloy (for example, platinum 90% / iridium 10% alloy), and is formed in a substantially hollow cylindrical shape. ing. The outer diameter of the stimulation electrode 108 is formed approximately equal to the outer diameter of the lumen insertion portion 110. The inner diameter of the stimulation electrode 108 needs to be longer than the diameter of the stylet lumen 106 so that the stimulation electrode 108 does not block the stylet lumen 106.

  Each stimulation electrode 108 is electrically connected to one end (end portion on the distal end side) of four conducting wires (not shown), and each other end of these conducting wires is connected to the stimulation circuit 113 of the stimulation device 103. Electrically connected. These four conductors are completely embedded in the body 104.

Next, the stimulation apparatus 103 will be described.
The stimulation device 103 includes a housing 107 and a stimulation circuit 113 housed and fixed in the housing 107.
The casing 107 is made of a relatively hard and biocompatible metal or resin, for example, a material such as titanium or epoxy, and has a substantially cylindrical shape. One end surface of the housing 107 is fixed to the surface near the base end 111 of the winding portion 105. In addition, the housing 107 has two holes extending in the axial direction from the one end surface to the other end surface. These two holes are suture holes 114, and a thread for sewing the stimulation device 103 to the living body is passed through the suture holes 114.

  The stimulation circuit 113 is a circuit in which a small component such as a custom IC is mounted on a circuit board, and generates an electrical stimulation signal. The stimulation circuit 113 is electrically connected to each conductor (not shown) embedded in the body 104 so as to supply the generated electrical stimulation signal to each stimulation electrode 108 independently. The electrical configuration of the stimulation circuit 113 will be described later with reference to FIG.

[2. Configuration of stimulation circuit]
Next, the electrical configuration of the stimulation circuit 113 housed in the stimulation apparatus 103 will be described with reference to FIG.
FIG. 3 is a functional block diagram centering on the stimulation circuit according to the first embodiment of the present invention.

  The stimulation circuit 113 includes a rechargeable battery 309, a coil unit 212, a charging unit 308, and a communication unit 302. Furthermore, a stimulation parameter setting unit 304, an electrode configuration setting unit 305, an oscillation unit 306, a control unit 303, and a switch unit 307 are provided.

  The rechargeable battery 309 is a rechargeable battery such as a lithium ion battery. Although not shown in FIG. 3, the rechargeable battery 309 supplies the accumulated power to each block constituting the stimulation circuit 113.

  The coil unit 212 is a resonance circuit composed of, for example, a coil and a capacitor. When charging the rechargeable battery 309, the coil unit 212 receives an electromagnetic wave for charging transmitted from an external controller (not shown). Then, an alternating current generated from the coil unit 212 with this reception is output to the charging unit 308. The coil unit 212 receives an electromagnetic wave on which predetermined information is transmitted, which is transmitted from an external controller (not shown), and the received electromagnetic wave is output from the coil unit 212 to the communication unit 302.

  The charging unit 308 has a built-in rectifier circuit, converts the alternating current output from the coil unit 212 into a direct current, and acquires power. Then, the rechargeable battery 309 is charged with the acquired power.

  The communication unit 302 demodulates the electromagnetic wave received by the coil unit 212 and extracts information placed on the electromagnetic wave. Then, the extracted information is output to the stimulation parameter setting unit 304 and the electrode configuration setting unit 305 via the control unit 303. Information output to the stimulation parameter setting unit 304 is information related to the stimulation intensity of the electrical stimulation signal (hereinafter referred to as “stimulation parameter”), and information output to the electrode configuration setting unit 305 is information related to the electrode configuration ( Hereinafter, this is referred to as “electrode configuration information”. Since the stimulation intensity of the electrical stimulation signal is determined by the pulse voltage, pulse current, pulse width, or frequency of the electrical stimulation signal, the stimulation parameter is a signal indicating values such as the pulse voltage. The electrode configuration information is a signal including information for changing the polarity of the electrical stimulation signal and information for causing the switch unit 307 to select the stimulation electrode 108 that outputs the electrical stimulation signal.

  The stimulation parameter setting unit 304 generates a stimulation intensity change signal for changing the stimulation intensity of the electrical stimulation signal generated by the oscillation unit 306 based on the stimulation parameter input from the communication unit 302.

  The electrode configuration setting unit 305 generates an electrode configuration selection signal for selecting the stimulation electrode 108 that outputs the electrical stimulation signal generated by the oscillation unit 306 based on the electrode configuration information input from the communication unit 302. The stimulus intensity change signal output from the stimulus parameter setting unit 304 is output to the oscillation unit 306, and the electrode configuration selection signal output from the electrode configuration setting unit 305 is output to the switch unit 307.

  The oscillation unit 306 generates an electrical stimulation signal based on the stimulation intensity change signal input from the stimulation parameter setting unit 304 and outputs the electrical stimulation signal to the switch unit 307.

  The switch unit 307 determines the stimulation electrode 108 that outputs the electrical stimulation signal input from the oscillation unit 306 based on the electrode configuration selection signal input from the electrode configuration setting unit 305. The control unit 303 is, for example, a microcomputer (hereinafter referred to as “microcomputer”) or the like, and controls each block of the stimulation circuit 113.

[3. Procedure for implanting electrical stimulator]
Next, an example of a procedure for performing electrical stimulation of spinal nerves from the epidural space with the electrical stimulation device 101 will be described with reference to FIGS.
4 to 7 are longitudinal sectional views of the human body showing the vicinity of the back.

  First, the doctor determines a target spinal stimulation site in advance based on the distribution of pain of the patient. Then, puncture is performed from the patient's back under fluoroscopy, and a split epidural needle 406 (hereinafter referred to as “dural epidural needle 406”) is inserted into the epidural space 405. Generally, the position where the epidural needle 406 is inserted into the epidural space 405 is selected to be lower than three vertebral bodies from the target stimulation site (see FIG. 4).

  Next, the doctor completely inserts the stylet 120 into the stylet lumen 106 formed on the electrode lead 102 and deforms the winding portion 105 into a substantially linear shape (see FIG. 2). As a result, the electrode lead can be easily implanted into the body.

  Here, the tip 112 (see FIG. 2) of the electrode lead 102 into which the stylet 120 is inserted is passed through the epidural needle 406, and the electrode lead 102 is inserted into the living body 404. The electrode lead 102 is inserted into the epidural space 405 by pushing the proximal end of the stylet 120 in the axial direction (see FIG. 5).

  Subsequently, the physician further pushes the proximal end of the stylet 120 in the axial direction to raise the electrode lead 102 into the epidural space 405 and bring the stimulation electrode 108 of the electrode lead 102 closer to the target stimulation site. Position.

  Next, the doctor performs nerve stimulation by operating an external controller (not shown) while moving the position of the stimulation electrode 108 little by little by inserting and removing the electrode lead 102 and the stylet 120 into the living body 404. At this time, the stimulation device 103 of the electrical stimulation device 101 generates an electrical stimulation signal having a predetermined intensity based on a doctor's operation, and the generated electrical stimulation signal is output to the stimulation electrode 108, so that the stimulation is performed. Neural stimulation is performed in a portion close to the position of the electrode 108. Then, the doctor determines the optimal position of the stimulation electrode 108 while listening to the patient's response to the nerve stimulation.

  Here, the doctor holds the electrode lead 102 and the stylet 120 so that the stimulation electrode 108 does not move from the determined optimal position, while the stylet 120 passes through the stylet lumen 106 of the electrode lead 102. The epidural needle 406 is removed from the living body 404 (see FIG. 6), the slit portion of the epidural needle 406 is torn, and the epidural needle 406 is removed from the surface of the electrode lead 102. At this time, the winding part 105 protruding from the body has an excessive length for removing the epidural needle 406 from the living body 404.

  Subsequently, the stylet 120 is taken out from the stylet lumen 106 of the electrode lead 102. Then, a restoring force that tries to return to a spiral shape works at the winding portion 105 of the electrode lead 102 in the living body 404, and the surrounding tissue of the living body 404 outside the epidural space 405 is wound by this restoring force. Pressed with 105. Thereby, the position of each stimulation electrode 108 of the electrode lead 102 is fixed. At this time, the winding part 105 also receives a force from the surrounding tissue of the living body 404 and maintains a substantially linear shape. The winding part 105 is held in a state where it is not inserted into the epidural space 405. Thereby, the electrode lead 102 can be easily removed from the living body 404 without damaging the tissue in the epidural space 405. On the other hand, the winding part 105 (hereinafter referred to as “projecting winding part”) outside the living body 404 returns to a spiral shape by its restoring force.

  After the above processing is completed, the doctor makes a small incision at the insertion site of the electrode lead 102 on the back side, and implants the protruding winding portion and the stimulator 103 under the small incision. The length of the turning part varies depending on the physical characteristics of the patient at that time and the position of the stimulation electrode 108. However, since the projecting winding part returns to a spiral shape, by pressing the projecting winding part in the direction of the rotation axis, the thickness of the projecting winding part in the direction of the rotation axis is adjusted to a certain extent. be able to. Thereby, irrespective of a patient's physical feature etc., the protrusion winding part and the irritation | stimulation apparatus 105 can be implanted completely subcutaneously.

  Finally, a thread (not shown) is passed through the suture hole 114 of the stimulator 103 so that the electrical stimulator 101 is fixed in a state where it is completely implanted in the living body 404, and the stimulator 103 is attached to the living body 404. After the tissue is sewn, the incision is sutured (see FIG. 7). This treatment is intended to prevent the stimulating device 103 from moving within the living body 404 or prevent an infection from being caused from the insertion port of the electrical stimulating device 101.

<Description of Second Embodiment of the Present Invention>
Next, an example of the second embodiment of the present invention will be described with reference to FIGS. The electrical stimulation apparatus 501 according to the second embodiment shown in FIGS. 8 and 9 has almost the same configuration as the electrical stimulation apparatus 101 according to the first embodiment. Description is omitted. Moreover, since the implantation procedure of the electrical stimulation apparatus 501 is the same as the implantation procedure of the electrical stimulation apparatus 101, description of the implantation procedure is also omitted.

[4. Configuration of electrical stimulation device]
First, the mechanical configuration of the electrical stimulation apparatus 501 according to the second embodiment will be described with reference to FIGS.
FIG. 8 is a perspective view showing the entire electrical stimulation device 501 according to the second embodiment of the present invention, and FIG. 9 is a perspective view showing a state in which the stylet of the electrical stimulation device shown in FIG. 8 is inserted. .

  Similar to the electrical stimulation apparatus 101 according to the first embodiment, the electrical stimulation apparatus 501 generates an electrical stimulation signal and stimulates nerves and the like in the living body with the stimulation signal. The electrical stimulation device 501 includes an electrode lead 502 and a stimulation device 503.

The electrode lead 502 will be described.
The electrode lead 502 includes a winding portion 504 instead of the winding portion 105 of the electrode lead 102 (see FIG. 1).

  The winding portion 504 has the same shape as the winding portion 105 and is a portion that is disposed in a tissue such as muscle, connective tissue, or fat outside the lumen when the electrical stimulation device 501 is implanted in the living body. . And the winding part 504 is being fixed to this irritation | stimulation apparatus 503 so that a part including the base end 506 may penetrate the irritation | stimulation apparatus 503. FIG. That is, the stylet lumen 106 that opens to the proximal end 506 of the winding portion 504 is exposed from the surface of the stimulation device 503. When the stylet 120 is completely inserted into the stylet lumen 106, the winding portion 504 is deformed from a spiral shape to a substantially linear shape as shown in FIG.

Next, the stimulation device 503 will be described.
The stimulating device 503 has a housing 505 instead of the housing 107 of the stimulating device 103 (see FIG. 1).
The housing 505 is made of a relatively hard and biocompatible metal or resin, for example, a material such as titanium or epoxy, has a substantially cylindrical shape, and has a substantially cylindrical hole penetrating the center of both end faces. Opened. The diameter of the hole is substantially equal to the outer diameter of the winding part 504, and a part of the winding part 504 including the base end 506 is accommodated and fixed in the hole.

<Description of the third embodiment of the present invention>
Next, an example of the third embodiment of the present invention will be described with reference to FIGS. The electrical stimulation apparatus 601 according to the third embodiment shown in FIGS. 10 and 11 is almost the same in configuration as the electrical stimulation apparatuses 101 and 501 according to the first and second embodiments. The description is omitted.

[5. Mechanical configuration of electrical stimulator]
First, the mechanical configuration of the electrical stimulation apparatus 601 according to the third embodiment will be described with reference to FIGS.
FIG. 10 is a perspective view showing the entirety of the electrical stimulation device 601 according to the third embodiment of the present invention, and FIG. 11 shows a state in which the stylet of the electrode lead constituting the electrical stimulation device shown in FIG. 10 is inserted. It is a perspective view shown.

  Similar to the electrical stimulation apparatuses 101 and 501, the electrical stimulation apparatus 601 generates an electrical stimulation signal and stimulates nerves and the like in the living body with the stimulation signal. The electrical stimulation device 601 includes an electrode lead 602 and a stimulation device 603.

The electrode lead 602 will be described.
The electrode lead 602 has a winding part 604 instead of the winding part 105 of the electrode lead 102 (see FIG. 1) according to the first embodiment.

  The winding portion 604 has the same shape as the winding portion 105 and is a portion that is placed in a tissue such as muscle, connective tissue, or fat outside the lumen when the electrical stimulation device 601 is implanted in the living body. . A connector portion 605 that can be coupled to the connector portion 607 of the stimulation device 603 is provided in a part including the base end 609 of the winding portion 604. The connector portion 605 includes four connector pins 608, and these four connector pins 608 are electrically connected to the four stimulation electrodes 108, respectively. Each connector pin 608 and each stimulation electrode 108 are connected by four conductive wires (not shown) completely embedded in the body 104. Note that, as in the first and second embodiments, the winding portion 604 is changed from a spiral shape to a substantially linear shape by completely inserting the stylet 120 into the stylet lumen 106 opened at the base end 609. (See FIG. 11).

Next, the stimulation device 603 will be described.
The stimulating device 603 includes a housing 606 instead of the housing 107 of the stimulating device 103 (see FIG. 1). The housing 606 is provided with a connector portion 607. The connector part 607 is formed so as to be connectable to the connector part 605 of the electrode lead 602. When the connector portion 607 is coupled to the connector portion 605, the connector pin 608 of the connector portion 605 is electrically connected to the stimulation circuit 113, and the stimulation circuit 113 is electrically connected to the stimulation electrode 108.

Next, a procedure for implanting the electrical stimulation device 601 when performing electrical stimulation of spinal nerves with the electrical stimulation device 601 will be described.
Since the first procedure is the same as the procedure described in FIGS. 4 and 5, the description thereof is omitted. After determining the optimal position of the stimulation electrode 108, the holder part (hand-held part) at the base end of the stylet 120 is removed, and the electrode lead 602 and the stylet 120 are held so that the position of the stimulation electrode 108 does not move. Then, the epidural needle 406 is removed from the living body 404 and further removed from the electrode lead 602. Here, since the electrode lead 602 can be inserted through the lumen of the epidural needle 406, it is not necessary to tear the slit portion of the epidural needle 406, and a normal epidural needle can also be used. Then, the stylet 120 is taken out from the stylet lumen 106 of the electrode lead 602, and the connector portion 605 of the electrode lead 602 is inserted into the connector portion of the stimulator 603 and coupled. The subsequent procedure is the same as the procedure described with reference to FIG.

<Modification>
In addition, in each embodiment mentioned above, the winding part formed in the helical form with which each winding radius is substantially equal is provided. However, as an alternative to this winding portion, it may be formed in a spiral shape having a winding radius that decreases from the proximal end 704 side to the distal end 705 side as in the winding portion 702 shown in FIG. Thereby, each winding surface of the winding part 702 can be overlapped on the same plane, and as a result, when performing the process of implanting the portion protruding from the body of the winding part 702 subcutaneously (see FIG. 7), The thickness of the winding part 702 can be reduced.

  Furthermore, as shown in FIG. 12B, a guard 703 that protrudes from the end surface on the distal end 705 side of the stimulation apparatus 103 may be provided. This guard is formed of a flexible and biocompatible material, for example, a resin material such as silicone or polyurethane, in a hollow, substantially cylindrical shape. Thereby, when the part which protruded from the body of the winding part 702 as mentioned above is implanted subcutaneously, the said winding part 702 will be accommodated in the guard 703. Thereby, the winding part 702 accommodated in the guard 703 can be prevented from moving. The guard 703 may have a notch for inserting the stylet into the stylet lumen at a position close to the base end 704 of the winding portion 702.

  In each embodiment of the present invention, the stylet can be used when the electrical stimulation apparatus is implanted in the living body by providing the electrode lead with the stylet lumen. Therefore, the electrical stimulation device can be more easily implanted into the body, and the accuracy of the placement of the stimulation electrode in the living body can be further improved.

  Moreover, in 3rd embodiment of this invention, the electrode lead and the stimulator are formed so that attachment or detachment is possible. For this reason, when the electrical stimulation device is implanted in the living body, only the electrode lead can be implanted first. Therefore, the epidural needle used for implantation of the electrode lead can be removed from the electrode lead without tearing. This eliminates the need to provide an extra portion in the wound portion to tear the epidural needle. As a result, the axial length of the winding portion can be made shorter than in the first and second embodiments.

  Moreover, in the third embodiment of the present invention, as described above, the epidural needle used for implanting the electrode lead can be pulled out from the electrode lead without tearing, so that it is used during implantation. It goes without saying that the epidural needle need not be divided or slitted.

  Further, in each of the above-described embodiments, when the electrode lead is inserted into the living body, the electrical stimulation device is directly passed through the epidural needle. However, the epidural needle is passed through the peel-away sheath in advance. After puncturing with the puncture needle integrated in the state, the epidural needle is removed leaving the peel-away sheath, and the electrical stimulation device is passed through this peel-away sheath so that the peel-away sheath is removed. It is possible to tear easily, and it is possible to reduce the burden on the electrode lead such as pulling at the time of tearing.

  In each of the embodiments described above, a rechargeable battery is used as a power source. However, a primary battery may be used instead of the rechargeable battery, or a capacitor is used instead of the rechargeable battery, and power is always supplied from an external controller. It may be operated while receiving.

  Moreover, in each embodiment mentioned above, it is not necessary to form in a spiral form for a predetermined distance from the base end part of a winding part.

  As mentioned above, although the example of each embodiment of the present invention was explained, the present invention is not limited to the above-mentioned each embodiment, and it is not limited to the scope of the present invention described in the claims. Needless to say, modifications and application examples are included.

DESCRIPTION OF SYMBOLS 101,501,601 ... Electrical stimulator, 102,502,602 ... Electrode lead, 103,503,603 ... Stimulator, 104 ... Body, 105,504,604,702 ... Winding part, 106 ... Stylet lumen , 107, 505, 606 ... casing, 108 ... stimulation electrode, 109 ... elongated body, 110 ... lumen insertion part, 113 ... stimulation circuit, 114 ... suture hole, 120 ... stylet, 212 ... coil part, 302 ... Communication unit 303 ... Control unit 304 ... Stimulus parameter setting unit 305 ... Electrode configuration setting unit 306 ... Oscillation unit 307 ... Switch unit 308 ... Charging unit 309 ... Rechargeable battery 404 ... Living body 405 ... Dura mater Outer cavity, 406 ... Epidural needle, 605, 607 ... Connector part, 608 ... Connector pin, 703 ... Guard

Claims (9)

An electrical stimulation device that is placed in a living body with an electrode lead made of a flexible elongated body and a stimulation device that generates a stimulation signal to be supplied to the electrode lead,
The electrode lead is
A lumen insertion part having a stimulation electrode for stimulating nerves and / or muscles in a living body;
A winding portion provided on a proximal end side with respect to the lumen insertion portion and having a continuous curved structure; and
The stimulator is
An electrical stimulation apparatus comprising a stimulation circuit that is electrically connected to the stimulation electrode and applies the stimulation signal to the stimulation electrode. The electrode lead is open at the base end, and a lumen is formed in the inside up to the vicinity of the tip.
The electrical stimulation device according to claim 1, wherein the continuous curved structure in the winding portion is deformed into a substantially linear shape by inserting a stylet into the lumen. The electrical stimulation device according to claim 1, wherein the continuous curved structure in the winding part is a spiral structure. The electrical stimulation device according to claim 1, wherein the continuous curved structure in the winding part is a spiral structure. When the electrode lead is placed in the living body, at least a part of the lumen insertion part is located in the lumen of the living body, and the winding part is located outside the lumen,
The electrical stimulation device according to any one of claims 1 to 4, wherein the wound portion compresses surrounding tissue outside the lumen. The electrical stimulation device according to claim 5, wherein the lumen is an epidural space. The stimulation device further includes a housing that houses the stimulation circuit, and the housing has a plane connected to a proximal end portion of the electrode lead;
The electrical stimulation device according to any one of claims 1 to 6, wherein a guard that accommodates at least a part of the continuous curved structure in the winding portion is formed on a plane of the casing. The electrode lead and the stimulation device each include a connector part that detachably connects the electrode lead and the stimulation device,
8. When the electrode lead and the stimulation device are connected by the connector unit, the stimulation electrode of the connector unit and the stimulation circuit of the stimulation device are electrically connected. The electrical stimulation apparatus as described in. An electrode lead made of a flexible long body and placed in a living body,
A lumen insertion portion having a stimulation electrode to which a stimulation signal generated by an external stimulation device is applied;
An electrode lead comprising: a winding portion provided on a proximal end side with respect to the lumen insertion portion and having a continuous curved structure.

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