JP5540317B2 - Conductive buffer material, electrode mechanism - Google Patents

Description

  The present invention relates to an electrode for nerves, an electroconductive buffer material for winding around a nerve bundle or a part of a peripheral nerve, an electrode jig for measuring or stimulating the nerve bundle or peripheral nerve via the electroconductive buffer material, The present invention relates to an electrode mechanism and a method of using the electrode mechanism.

  As a typical peripheral nerve type nerve electrode used to give electrical stimulation to peripheral nerve cells in various parts of the body and to measure electrical activity, it is made from an insulating material such as silicon using a microfabrication technology. (See Non-Patent Document 1) is known. Peripheral nerve-type nerve electrodes include an insertion type that inserts a nerve electrode into a nerve bundle, a cuff type that winds the nerve electrode around the nerve bundle, and an electrode hole arranged in the regeneration path using the self-regenerative function of a cut nerve fiber There is a regeneration type that passes nerve fibers. However, when a peripheral nerve type nerve electrode made of a material such as hard silicon is placed or fixed to the peripheral nerve, it cannot follow the movement of the peripheral nerve or the surrounding area of the peripheral nerve, damage the living tissue, or measure or stimulate There has been a problem that stable measurement and stimulation are difficult because the target nerve is killed, and further, the movement outside the measurement or stimulation possible range is attracted. Accordingly, peripheral nerve type flexible nerve electrodes (see Non-Patent Document 2 and Patent Document 1) using a flexible insulating material such as parylene and polyimide have been developed in order to improve the followability to the movement around the peripheral nerve and the indwelling portion. I came.

  Here, the cuff type peripheral nerve type flexible nerve electrode of Patent Document 1 will be briefly described. FIG. 1 is a diagram showing the structure of a cuff-type peripheral nerve type flexible nerve electrode of Patent Document 1. As shown in FIG. FIG. 1A is a plan view, and FIG. 1B is a cross-sectional view along BB. FIG. 2 shows the state of attachment to the nerve bundle. The cuff type peripheral nerve type flexible nerve electrode 60 of Patent Document 1 includes a first insulating layer 11, a second insulating layer 12, and a plurality of electrode wirings 13 each including an electrode portion 14 and a wiring portion 15. The Then, as shown in FIG. 2, by winding around the nerve bundle 91, the electrode portion 14 in contact with or approaching the nerve bundle 91 electrically stimulates the nerve bundle 91, and the electrical activity of the nerve bundle 91 is also increased. measure. As shown in FIG. 1 (A), the cuff-type peripheral nerve type flexible nerve electrode 60 is fixed to the nerve bundles of the first insulating layer 11 and the second insulating layer 12 so as to be fixed when wound around the nerve bundle 91. Protrusions 61 and hooking holes 62 are provided in pairs at both end edge lines that come into contact with each other, and can be fixed by hooking the protrusions 61 into the hooking holes 62 as shown in FIG.

JP 2009-285154 A

Tayfun Akin et al. "A Micromachined Silicon Sieve Electrode for Nerve Regeneration Applications", IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, APRIL 1994, VOL.41, No.4, p.305-313. Francisco J. Rodriguez et al. "Polyimide cuff electrodes for peripheral nerve stimulation", Journal of Neuroscience Methods, 2000, 98, p105-118.

  However, the prior art has a problem caused by the fixed positional relationship of the electrodes. Specifically, for example, measurement and stimulation of peripheral nerves having myelinated nerve fibers are performed through a Lambier diaphragm that is a constriction of the myelin sheath, which is an insulator, but the Lambier diaphragm is not provided for each nerve fiber. Arranged in the rules. Therefore, it has been difficult to place an appropriate electrode at the position of the Lambier diaphragm with respect to the nerve bundle. Moreover, when the nerve bundle or the peripheral nerve moved, the electrode could not be moved. As a method for solving these problems and surely arranging them at appropriate positions, a method of arranging a number of electrodes and selecting electrodes at appropriate positions can be considered. However, this method requires an enormous number of electrodes.

  An object of the present invention is to make it possible to adjust (change) the position of an electrode when measuring or stimulating a nerve bundle or a peripheral nerve.

  The conductive cushioning material of the present invention is for winding around a nerve bundle or a part of a peripheral nerve. The conductive cushioning material of the present invention is in the form of a sheet, and the resistance in the front and back direction of the sheet is sufficiently smaller than the resistance in the other direction (for example, anisotropic conductive rubber, anisotropic A buffer portion formed of conductive conductive silicon, anisotropic conductive urethane, and the like, and an end fixing means for maintaining the state where the buffer portion is wound in a cylindrical shape. In the case of measurement, “sufficiently small” means that when a voltage is applied to one point inside a cylindrically wound buffer portion (or when a current flows), the buffer corresponding to that point. This means that the voltage (or flowing current) applied to the other points outside the buffer portion is smaller than the voltage applied to one point outside the buffer portion (or flowing current) so as not to affect the measurement. In addition, when stimulating, when a voltage is applied to one point outside the cylindrically wound buffer part (or when a current is passed), one point inside the buffer part corresponding to that point This means that the voltage (or flowing current) applied to the other inner point of the buffer is small enough not to affect the nerve bundle or peripheral nerve. The end fixing means is, for example, a fixing hole formed at one end of the buffer part and an end opposite to the fixing hole of the buffer part. What is necessary is just to comprise with a string.

  The electrode jig of the present invention has a jig body, one or more electrodes, and wiring connected to each electrode. The jig body has at least a surface formed of an insulator, and has an arcuate arc part and a grip part for gripping the electrode jig. The electrode is disposed on the inner surface of the arc portion of the jig body.

  The electrode mechanism of this invention is comprised so that the electrode of an electrode jig may contact the outer periphery of the buffer part wound by the cylinder shape. And an electrode mechanism should just be used as follows. First, a buffer is wrapped around a nerve bundle or a part of a peripheral nerve. The electrode of the electrode jig is brought into contact with the position of the outer periphery of the buffer portion corresponding to the position of the nerve bundle or peripheral nerve to be measured or stimulated. Then, the nerve bundle or the peripheral nerve is measured or stimulated with the electrode.

  According to the conductive cushioning material of the present invention, a nerve bundle or a peripheral nerve is wound by a cushioning portion formed of a sheet-like anisotropic conductive flexible material whose resistance in the front and back directions is sufficiently smaller than the resistance in other directions. It can be in the state. Therefore, the target position can be measured or stimulated by bringing the electrode into contact with the outer point corresponding to the inner point of the buffer portion in contact with the position of the nerve bundle or peripheral nerve to be measured or stimulated. That is, when measuring or stimulating the nerve bundle or the peripheral nerve, the position of the electrode can be adjusted without damaging the nerve bundle or the peripheral nerve. According to the electrode jig of the present invention, one or more electrodes can be arranged along the outer periphery of the buffer portion wound in a cylindrical shape. Moreover, the area of the electrode can also be selected as appropriate. Therefore, if one or more electrode jigs of the present invention are used, an arbitrary number of electrodes having an arbitrary area can be arranged at an arbitrary position of the nerve bundle or the peripheral nerve.

The figure which shows the structure of the conventional cuff type peripheral nerve type | mold flexible nerve electrode. The figure which shows the state which mounted | wore the nerve bundle | flux with the conventional cuff type peripheral nerve type | mold flexible nerve electrode. The figure which shows the structural example of the electroconductive buffer material of this invention. The figure which shows the state which wound the electroconductive buffer material of this invention around the nerve bundle. The figure which shows the state which wound the conductive buffer around the peripheral nerve and nerve fiber which have a myelinated nerve fiber. The figure which shows the 1st structural example of the electrode jig of this invention. The figure which shows the 2nd structural example of the electrode jig of this invention. The figure which shows the electrode jig | tool which combined the electrode jig | tool of FIG. The figure which shows a mode when a nerve bundle is measured or stimulated using the electroconductive buffer material of FIG. 3, and the electrode jig of FIG. The figure which shows a mode when measuring or stimulating the peripheral nerve which has a myelinated nerve fiber using the conductive buffer material of FIG. 3, and the three electrode jigs of FIG.

  Hereinafter, embodiments of the present invention will be described in detail. In addition, the same number is attached | subjected to the structure part which has the same function, and duplication description is abbreviate | omitted.

<Conductive cushioning material>
In FIG. 3, the structural example of the electroconductive buffer material of this invention is shown. FIG. 3A is a plan view of the conductive buffer material, and FIG. 3B is a cross-sectional view taken along the line AA. The conductive cushioning material 100 is in the form of a sheet, and an anisotropic conductive flexible material (for example, anisotropic conductive rubber, anisotropic conductive silicon, anisotropic) whose resistance in the front and back directions is sufficiently smaller than the resistance in other directions. A shock-absorbing portion 110 formed of a conductive conductive urethane, and an end fixing means for maintaining the state in which the shock-absorbing portion 110 is wound in a cylindrical shape. “The resistance in the front and back direction is sufficiently smaller than the resistance in the other direction” means that when a voltage is applied to one point inside the buffer portion 110 wound in a cylindrical shape (or current) The voltage (or flowing current) applied to other points outside the buffer unit 110 is measured as compared to the voltage (or flowing current) applied to one point outside the buffer unit 110 corresponding to that point. It means that it becomes small so as not to affect. In the case of stimulation, when a voltage is applied to one point outside the buffer part 110 wound in a cylindrical shape (or when a current is passed), the inside of the buffer part 110 corresponding to that point This means that compared to the voltage (or flowing current) applied to one point, the voltage (or flowing current) applied to the other inner point of the buffer 110 is so small that it does not affect the nerve bundle or peripheral nerve. . In addition, it is better that the buffer unit 110 is sized so that the buffer unit 110 does not overlap as much as possible when the buffer unit 110 is wound so as to be in close contact with the nerve bundle or the peripheral nerve. Further, the end fixing means may be a means in which the buffer portions 110 are difficult to overlap.

  For example, the end fixing means may be configured by fixing holes 130-1, 130-2, 130-3 and fixing strings 120-1, 120-2, 120-3. The fixing hole 130 is formed at one end of the buffer portion 110. The fixed string 120 includes a string part 121 and a drop prevention claw 122, and is formed at an end on the opposite side of the fixing hole 130 of the buffer part. The fixed string 120 has a structure that can pass through the fixed hole 130 and cannot move in the direction in which the fixed string 120 is removed by the removal preventing claw 122. And the magnitude | size of the cylinder which the buffer part 110 makes can be changed by pulling the fixed string 120. In FIG. 3A, three fixing holes 130 and three fixing strings 120 are formed, but other numbers may be used. The number of the fixing holes 130 and the fixing strings 120 may be appropriately determined in consideration of the size of the buffer portion 110 and the like. Further, the end fixing means may have other configurations such as the hooking hole 62 and the protrusion 61 shown in FIGS.

  The anisotropic conductive flexible material is mainly composed of conductive particles (filler) 115 and an adhesive (binder). The filler 115 may be a metal core (such as nickel or nickel plated with gold) or a resin core subjected to gold plating (such as styrene or acrylic). The adhesive is a flexible material such as non-conductive synthetic rubber, silicon, or urethane, and is used to fix the filler 115 in an arrayed state. In FIG. 3B, the fillers 115 are arranged in the vertical direction. Therefore, the resistance in the vertical direction is small (for example, several Ω), but the resistance in the horizontal direction is large (for example, several MΩ or more). Further, the particle diameter and the orientation pitch (pitch where the fillers are arranged) may be determined according to the size of the nerve bundle or peripheral nerve. For example, the particle size may be several μm and the orientation pitch may be about 10 μm. The thickness of nerve bundles and peripheral nerves varies, and some have a diameter of about 10 μm and others have a diameter of 1 mm or more. Therefore, what is necessary is just to determine the thickness of the buffer part 110 suitably from the nerve bundle used as a sample, or the thickness of the peripheral nerve. At the time of filing this application, a thin film using an anisotropic conductive flexible material (for example, anisotropic conductive rubber, anisotropic conductive silicon, anisotropic conductive urethane, etc.) has been put into practical use up to a few tens of μm. ing. Therefore, the present invention cannot be used for all nerve bundles and peripheral nerves, but can be used for many nerve bundles and peripheral nerves. The extent to which the present invention can be used for thin nerve bundles and peripheral nerves depends on the technical level of thinning the anisotropic conductive flexible material.

  FIG. 4 is a diagram showing a state where a conductive buffer material (buffer portion) is wound around a nerve bundle, and FIG. 5 is a diagram showing a state where a conductive buffer material (buffer portion) is wound around peripheral nerves and nerve fibers having myelinated nerve fibers. FIG. FIG. 5 (A) shows the structure of a peripheral nerve having myelinated nerve fibers, and FIG. 5 (B) shows a state in which a conductive cushioning material is wound around a part of an axon (however, an end portion). The fixing means is omitted). When winding the conductive buffer material 100, the following procedure may be used. The conductive buffer material 100 is selected so that the size of the buffer 110 matches the thickness of the nerve bundle and the range to be measured or stimulated. Then, the buffer 110 is wound around the nerve bundle 91, and the fixed strings 120-1, 120-2, 120-3 are inserted into the fixed holes 130-1, 130-2, 130-3, respectively. And the buffer part 110 closely_contact | adheres to a nerve bundle | flux as shown in FIG. 4 by pulling the fixed string 120-1,120-2,120-3 appropriately. Thus, if the conductive buffer material 100 is a nerve bundle thicker than the diameter limited by the thickness and softness of the buffer part 110, it can be wound so that the buffer part 110 is brought into close contact with the nerve bundle. In addition, what is necessary is just to cut | disconnect the excess fixed string 120-1,120-2,120-3. A peripheral nerve having a myelinated nerve fiber includes a nerve cell 93 and an axon 94 as shown in FIG. 5A. The axon 94 includes a plurality of myelin sheaths 96 which are insulators, and a myelin sheath 96. It is composed of a Lambier diaphragm 95 which is a constricted portion between them. Then, measurement and stimulation of peripheral nerves having myelinated nerve fibers are performed through a Lambier diaphragm 95. If the axon 94 is thicker than the diameter limited by the thickness and softness of the buffer part 110, the buffer part 110 can be wound in close contact with the axon 94 so as to include the position of the Lambier diaphragm 95. (See FIG. 5B).

  Since the conductive buffer material of the present invention has such a configuration, the electrode can be brought into contact with an outer point corresponding to an inner point of the conductive buffer material that is in contact with a position to be measured or stimulated of the nerve bundle or peripheral nerve. For example, the target position can be measured or stimulated. That is, when measuring or stimulating the nerve bundle or the peripheral nerve, the position of the electrode can be adjusted without damaging the nerve bundle or the peripheral nerve.

<Electrode jig>
FIG. 6 is a diagram showing a first configuration example of the electrode jig of the present invention, and FIG. 7 is a diagram showing a second configuration example of the electrode jig of the present invention. The electrode jig 210 in FIG. 6 includes a jig main body 211, an electrode 215, and a wiring 216 connected to the electrode 215. The jig body 211 is formed of an insulator at least on the surface, and includes an arcuate arc part 212 and a grip part 213 for gripping the electrode jig 210. The electrode 215 is disposed on the inner surface of the arc portion 212 of the jig main body 211. The wiring may be arranged in any way as long as it is formed so that the electrode can be connected to the outside. The arc part 212 in the figure is an arc of 180 degrees, but it is accurate as long as the buffer part 110 wound around the nerve bundle or the peripheral nerve and the inner surface of the arc part 212 can be brought into contact with each other. It does not have to be a circular arc, and other angles may be used. In addition, the grip portion 213 has a rod shape in the figure, but may have a shape other than the rod shape as long as it is easily attached to a mechanism for gripping and moving the electrode jig 210.

  7 has a jig body 211, seven electrodes 215-1,..., 7 and wirings 216-1,. The electrodes 215-1,..., 7 are arranged on the inner surface of the arc portion 212 of the jig main body 211. The electrode jig 210 has one electrode and the electrode jig 220 has seven electrodes, but the number of electrodes is not limited to these. The number of electrodes to be measured or stimulated may be provided on the inner surface of the arc portion 212 of the jig body 211 as many as the number of electrodes to be measured or stimulated. FIG. 8 is a view showing an electrode jig in which two electrode jigs of FIG. 7 are combined. The electrode jig 320 includes electrode jigs 220-1 and 220-2, and the electrodes can be arranged in a range of 360 degrees. Different electrode jigs may be combined.

  Since the electrode jig of this invention is such a structure, one or more electrodes can be arrange | positioned along the outer periphery of the electroconductive buffer material wound by the cylinder shape. Moreover, the area of the electrode can also be selected as appropriate.

<Electrode mechanism>
The electrode mechanism of the present invention has at least a conductive buffer material and one or more electrode jigs. The electrode mechanism may have electrode gripping / moving means (not shown) for gripping and moving the electrode jig in addition to these. For example, the electrode gripping / moving means may be a means capable of adjusting a minute position manually using a micrometer or the like and fixing the electrode at the position. Alternatively, it may be a means for automatically moving to a position indicated by a numerical value input by a person and stopping. A method using this electrode mechanism will be described below. First, a buffer part is wound around a nerve bundle or a part of a peripheral nerve, and an electrode jig with an appropriate curvature of the arc part and the arrangement and area of the electrodes is selected. Then, the electrode of the electrode jig is brought into contact with the position of the outer periphery of the buffer portion corresponding to the position of the nerve bundle or peripheral nerve to be measured or stimulated, and the nerve bundle or the peripheral nerve is measured or stimulated with the electrode.

  FIG. 9 shows a state when a nerve bundle is measured or stimulated using the conductive buffer material of FIG. 3 and the electrode jig of FIG. If the size of the buffer 110 is matched to the thickness of the nerve bundle 91, the buffer 110 can be wound in a state of being in close contact with the nerve bundle 91 as shown in FIG. And if the electrode jig | tool 220 with the appropriate curvature of the circular arc part 212 is selected, the electrode 215-1, ..., 7 of the electrode jig | tool 220 can be made to contact the buffer part 110 outer periphery. Moreover, since the buffer part 110 is wound around the nerve bundle 91, the position of the electrode jig 220 can be adjusted without damaging the nerve bundle 91. Therefore, the electrode can be surely arranged at the position to be measured or stimulated, and the position of the electrode jig 220 can be changed without damaging the nerve bundle 91 even when the nerve bundle 91 moves in the middle. it can. Furthermore, when the range to be measured or stimulated is changed or the electrode is dirty, the electrode can be easily replaced.

  FIG. 10 shows a state when measuring or stimulating a peripheral nerve having a myelinated nerve fiber using the conductive buffer material of FIG. 3 and the three electrode jigs of FIG. If the size of the buffer portion 110 is adjusted to the thickness of the shaft 94, the buffer portion 110 can be wound in close contact with the shaft 94 as shown in FIG. If the electrode jig 210 having an appropriate curvature of the arc part 212 is selected, the electrode 215 of the electrode jig 210 can be brought into contact with the outer periphery of the buffer part 110. Moreover, since the buffer part 110 is wound around the shaft 94, the position of the electrode jig 210 can be adjusted without damaging the shaft 94. Therefore, the electrode 215 can be reliably arranged at the position of the Lambier diaphragm 95, and the position of the electrode jig 210 can be adjusted without damaging the axis 94 even if the axis 94 moves in the middle. Can change. Further, if a plurality of electrode jigs 210 are used as shown in FIG. 10, a plurality of lambier diaphragms 95 can be measured or stimulated simultaneously. Further, when the electrode is dirty, the electrode can be easily replaced.

  As described above, according to the conductive cushioning material of the present invention, the nerve bundle or the peripheral nerve is buffered with a sheet-like anisotropic conductive flexible material whose resistance in the front and back directions is sufficiently smaller than the resistance in the other directions. It can be in a state of being wound by a part. Therefore, the target position can be measured or stimulated by bringing the electrode into contact with the outer point corresponding to the inner point of the buffer portion in contact with the position of the nerve bundle or peripheral nerve to be measured or stimulated. That is, when measuring or stimulating the nerve bundle or the peripheral nerve, the position of the electrode can be adjusted without damaging the nerve bundle or the peripheral nerve. According to the electrode jig of the present invention, one or more electrodes can be arranged along the outer periphery of the buffer portion wound in a cylindrical shape. Moreover, the area of the electrode can also be selected as appropriate. Therefore, if one or more electrode jigs of the present invention are used, an arbitrary number of electrodes having an arbitrary area can be arranged at an arbitrary position of the nerve bundle or the peripheral nerve.

  The present invention can be used in the field of nerve electrodes for measuring or stimulating nerves.

DESCRIPTION OF SYMBOLS 100 Conductive buffer material 110 Buffer part 115 Filler 120 Fixed string 121 String part 122 Prevention claw 130 Fixing hole 210, 220, 320 Electrode jig 211 Jig body 212 Arc part 213 Grasping part 215 Electrode 216 Wiring

Claims (3)

A conductive cushion for wrapping around a nerve bundle or part of a peripheral nerve,
A buffer portion formed of an anisotropic conductive flexible material that is in the form of a sheet and has a resistance in the front and back direction sufficiently smaller than the resistance in the other direction;
A conductive cushioning material comprising: an end fixing means for maintaining the state in which the cushioning portion is wound in a cylindrical shape. The conductive cushioning material according to claim 1,
The end fixing means is
A fixing hole formed at one end of the buffer portion;
A conductive buffer material, comprising: a fixed string formed at an end of the buffer portion on the opposite side of the fixing hole, and penetrating the fixing hole, and having a pull-out preventing claw. The conductive buffer material according to claim 1 or 2, and an electrode jig,
The electrode jig is
At least the surface is formed of an insulator, and a jig body having an arcuate arc part and a grip part for gripping the electrode jig,
One or more electrodes disposed on the inner surface of the arc portion of the jig body;
Wiring connected to each of the electrodes,
The electrode mechanism, wherein the electrode of the electrode jig is brought into contact with an outer periphery of the buffer portion wound in a cylindrical shape.

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