JP5839939B2 - Introducing device and nerve stimulation electrode placement system. - Google Patents

Description

  The present invention relates to an introducer and a nerve stimulation electrode placement system for placing an electrode for stimulating nerves in the body.

  Conventionally, stimulation that performs treatment by applying electrical stimulation directly or indirectly to living tissue (linear tissue) such as nerve tissue and muscle, such as a nerve stimulation device, a pain relief device, an epilepsy treatment device, and a muscle stimulation device. Generators are known. These stimulation generators have a power source inside and are usually used by being implanted in a living body together with a stimulation electrode for transmitting electrical stimulation.

In general, a stimulation electrode provides at least one electrode for applying electrical stimulation to biological tissue or detecting electrical excitation generated in biological tissue, an electrical connector for electrically connecting to a stimulation generator, and an electrode And a lead portion for transmitting electrical stimulation provided between the device and the stimulus generator.
For example, in Patent Document 1, when the heart generates bradycardia, the heart is stimulated to increase the heart rate, and when the heart generates tachycardia or fibrillation, the vagus nerve is stimulated to decrease the heart rate. An implantable heart treatment device is disclosed. In Patent Document 1, a cardiac stimulation electrode is disposed in the myocardium or the atrium. It is considered that the right central position of the cervical region or the outer carotid artery is suitable as a site where the nerve stimulation electrode is wound and placed.

JP 2004-173790 A

In the prior art in this field, the nerve stimulation electrode is often placed at a site where the electrode can be placed under visual observation. For example, if it is a nerve stimulation electrode for stimulating the vagus nerve of the heart, as described in Patent Document 1, it is placed in the neck or the like.
However, since the vagus nerve has branches in its route that branch to the internal organs of the neck, chest, and abdomen, when the vagus nerve is stimulated in the neck, in addition to the heart, which is the tissue to be treated, the cervix, etc. Stimulation may also be transmitted to other organs. As a result, there is a problem that the patient may exhibit reflex subjective symptoms such as clogging of the throat and coughing, contributing to a decrease in the patient's QOL (quality of life).

  The present invention has been made in view of the above-described circumstances, and an introducer that enables placement of a nerve stimulation electrode so as to reduce stimulation to a tissue that is not a treatment target, and the introducer It is an object to provide a nerve stimulation electrode placement system comprising:

In order to solve the above problems, the present invention proposes the following means.
The introducer of the present invention is an introducer for introducing a nerve stimulation electrode into a target nerve tissue, and has a cylindrical main body having a lumen, a blunt incision portion for blunt dissection of a biological tissue, and is transparent. An incision member formed to be attached to the distal end portion of the main body and at least one of the outer surface of the front end portion of the main body and the outer surface of the incision member . And a discrimination electrode for discriminating whether or not .

In the introduction tool, it is more preferable that the discrimination electrode is formed over the entire circumference of the main body.
In the introduction tool, it is more preferable that the discrimination electrode is formed only in a partial range in the circumferential direction of the main body.
Further, in the introduction tool, at least one of the proximal end portion of the main body and the incising member in the circumferential direction of the lumen has the circumferential direction in which the discrimination electrode is formed at the same position as the discrimination electrode It is more preferable that an index portion indicating a position is formed.
In the introduction tool, it is more preferable that the discrimination electrode is formed to extend in the longitudinal direction of the main body.

The nerve stimulation electrode placement system according to the present invention is a nerve stimulation electrode placement system for placing a nerve stimulation electrode in a desired target nerve tissue, and includes the introduction tool and the incision member as described above. an observation portion which is inserted into observable to the introducer around the cutting member, said rotatably and disposed relatively movably in the axial direction with respect to the introducer to its axis line, near the target neural tissue And a peeling portion for removing the surrounding tissue.

In the above-described nerve stimulation electrode placement system, it is more preferable to include a monitoring unit that measures the state of the living body and displays the measurement result.
In the above nerve stimulation electrode placement system, the measurement result may be an electrocardiogram.
In the above nerve stimulation electrode placement system, the measurement result may be an electromyogram.

  According to the introducer and the nerve stimulation electrode placement system of the present invention, the nerve stimulation electrode can be placed so as to reduce the stimulation to the tissue not to be treated.

It is a figure showing the whole nerve stimulation electrode placement system composition of a 1st embodiment of the present invention. It is a figure which shows the front end side of the same nerve stimulation electrode placement system in a partial cross section. It is a front view of the tip side. It is an enlarged view which shows the front end side of a peeling part. It is a figure which shows the nerve stimulation electrode in which the stylet was inserted in a partial cross section. It is sectional drawing in the AA of FIG. It is a figure which shows the operation | movement at the time of use of the same nerve stimulation electrode placement system. It is a figure which shows the access path | route of the same nerve stimulation electrode placement system, and surrounding organ arrangement | positioning. (A) And (b) is a figure which shows the peeling process by a peeling part both. It is a figure which shows the operation | movement at the time of the indwelling of the same nerve stimulation electrode. It is a figure which shows the operation | movement at the time of the indwelling of the same nerve stimulation electrode. It is a side view of the principal part of the nerve stimulation electrode placement system in the modification of 1st Embodiment of this invention. It is a side view of the principal part of the nerve stimulation electrode placement system in the modification of 1st Embodiment of this invention. It is a side view of the principal part of the nerve stimulation electrode placement system in the modification of 1st Embodiment of this invention. It is a figure which shows the whole structure of the nerve stimulation electrode placement system of 2nd Embodiment of this invention. It is a figure which shows the whole structure of the nerve stimulation electrode placement system of 3rd Embodiment of this invention.

(First embodiment)
Hereinafter, a first embodiment of a nerve stimulation electrode placement system according to the present invention will be described with reference to FIGS.
As shown in FIG. 1, the present nerve stimulation electrode placement system (hereinafter simply referred to as “placement system”) 1 passes through a tissue such as a connective tissue to a desired nerve tissue such as a vagus nerve ( Hereinafter, it is simply referred to as “electrode”.) Each treatment for introducing and placing 100 is performed. The indwelling system 1 is treated so that the electrode 100 can be indwelled with respect to the target nerve tissue, the introducer 10 of the present embodiment formed in a substantially cylindrical shape, the observation unit 20 inserted into the introducer 10. And a stylet (electrode operation member) 40 for performing an indwelling operation of the electrode 100.

The introducer 10 includes a substantially cylindrical main body 11, a transparent cap (cutting member) 12 attached to the front end of the main body 11, and discrimination electrodes 18 and 19 provided on the outer surface of the front end of the main body 11. I have.
2 and 3, the main body 11 includes a first lumen (first lumen) 13 into which the observation unit 20 is inserted and a second lumen (second lumen) through which the peeling unit 30 is inserted. ) 14 and a third lumen (electrode lumen) 15 through which the electrode 100 and the stylet 40 are inserted, and a known multi-lumen tube or the like can be used. . The first lumen 13, the second lumen 14, and the third lumen 15 are formed in a substantially cylindrical shape.
The material of the main body 11 is not particularly limited as long as it has a rigidity that allows advancement and retraction of a surrounding tissue, which will be described later, and a metal such as stainless steel, a resin, or the like can be suitably used. From the viewpoint of facilitating the introduction operation of the introducer 10, the outer diameter of the introducer 10 is preferably 6 millimeters (mm) or less.

The cap 12 is formed of a resin or the like so as to be transparent, and is attached to the distal end portion of the main body 11 so as to seal only the first lumen 13. The cap 12 may have a desired color as long as the cap 12 has transparency that allows the periphery of the cap 12 to be observed from the inserted observation unit 20. The cap 12 has a proximal-end-side cylindrical portion 12A connected to the main body 11 and a more-conical portion (blunt dissection portion) 12B, and the observation portion 20 inserted through the first lumen 13. Is capable of advancing and retracting the lumen of the cylindrical portion 12A and rotatable about its own axis with respect to the introducer 10. The surface on the distal end side of the lumen of the cylindrical portion 12A is formed so as to have a predetermined curvature in consideration of the performance of the observation portion 20, or an optical coating film is formed to illuminate the observation portion 20. You may comprise so that light (after-mentioned) may not interfere with observation.
The conical portion 12B has a distal end whose radius of curvature is set to about 0.2 mm, for example, and is not sharp. By pushing the introduction tool 10 with the conical portion 12B at the top, the indwelling system 1 can be introduced to the vicinity of the target tissue while bluntly incising the surrounding tissue existing around the cap 12. This operation will be described in detail in the description of the procedure.

The discrimination electrodes 18 and 19 are formed of a material that is stable in the living body, such as platinum, over the entire circumference of the main body 11. As shown in FIG. 1, the discrimination electrodes 18 and 19 are electrically connected to the discrimination power supply 5 via a wiring 5 a extending from the proximal end of the introduction tool 10. The discrimination power supply 5 applies a weak rectangular wave between the discrimination electrodes 18 and 19, for example, a voltage of 1 to 10 volts, a frequency of 10 to 20 hertz, and a frequency of 10 to 1000 microseconds. be able to.
Note that the discrimination electrodes 18 and 19 may be connected to a later-described nerve stimulation apparatus to which the electrode 100 is connected, and a voltage may be applied between the discrimination electrodes 18 and 19 by the nerve stimulation apparatus.

The observation unit 20 has an outer diameter that can be inserted into the first lumen 13, and includes an observation optical system 21 and an illumination unit 22 such as a light guide that illuminates the field of view of the observation optical system 21, as shown in FIG. At the tip. As shown in FIG. 1, the observation unit 20 is connected to the base imaging unit 23 by a known image guide or the like, and can acquire an image in the field of view of the observation optical system 21. The imaging unit 23 is connected to the monitor 24, and the video acquired by the imaging unit 23 is displayed on the monitor 24.
When the illumination unit 22 is a light guide, it is connected to a light source (not shown) provided in the imaging unit 23. Instead of the light guide, a light emitting member such as an LED may be mounted on the tip as the illumination means.
As the observation unit 20, a known endoscope apparatus can be suitably used as long as the outer diameter dimension is an appropriate value.

FIG. 4 is an enlarged view of the front end side of the peeling portion 30. The peeling part 30 has the elongate rod 31 and the spatula part 32 attached to the front-end | tip part of the rod 31, as shown in FIG.3 and FIG.4. The material of the rod 31 is not limited as long as it has a certain degree of rigidity that can advance and retreat in the axial direction, and a metal such as stainless steel, a resin, or the like can be suitably used.
The spatula portion 32 is formed in a plate shape or a sheet shape, and is attached so as to extend in a direction substantially orthogonal to the axial direction of the rod 31. The spatula portion 32 has a certain rigidity that can peel connective tissue around the nerve tissue (hereinafter also referred to as “peripheral tissue”), and is formed of the same material as that of the rod 31. be able to. The peripheral edge on the front end side of the spatula portion 32 extending from the rod 31 is formed so as not to be sharp like the front end of the conical portion 12B so that a later-described peeling operation can be performed bluntly.

The structure of the stylet 40 and the electrode 100 will be described. FIG. 5 is a partial cross-sectional view of the electrode 100 into which the stylet 40 is inserted, and FIG. 6 is a cross-sectional view taken along line AA of FIG.
The electrode 100 includes a long lead portion 101, an electrode portion 102 provided on the distal end side of the lead portion 101, and a support portion 103 that supports the electrode portion 102 so as to come into contact with a nerve tissue.

The lead portion 101 is formed in a substantially cylindrical shape having a lumen 104 made of polyurethane or the like having high stability in the living body, and the sturret 40 can be inserted into the lumen 104. The lumen 104 does not open to the distal end side of the lead portion 101, and the distal end portion of the lumen 104 is crushed in the radial direction. Thereby, the minimum dimension in the radial direction of the distal end portion is shorter than the dimension in the radial direction of the substantially cylindrical shape of the lumen 104.
The lead part 101 has a plurality of leads (not shown). In each lead, the conductive core wire is formed using a highly durable MP35N wire or 35MLT wire, and each core wire is covered with an insulating coating made of ETFE material to form each lead in the lumen 104. Has been placed. The distal end side of the lead is connected to the electrode portion 102, and the proximal end side of the lead is connected to a connector 105 for connecting to a nerve stimulation device (not shown). As the connector 105, a known connector is appropriately selected according to the nerve stimulation apparatus to be connected. For example, an IS1 connector can be used.
Instead of the above configuration, only the core wire without insulation coating may be embedded in the substantially cylindrical peripheral wall of the lead portion 101 to form a lead.

The configuration of the electrode unit 102 is not particularly limited as long as electrical stimulation can be applied to the contacted nerve tissue, but as shown in FIG. 5, a bipolar electrode having two electrodes, a negative electrode 102A and a positive electrode 102B. It is preferable that As a material for the negative electrode 102A and the positive electrode 102B, platinum that is stable in vivo is used. A titanium nitride (TiN) film having a fine concavo-convex structure is formed on the surface of each electrode 102A, 102B, and the impedance with the living body surface is lowered.
Each electrode 102A, 102B is exposed only on the side facing the nerve tissue at the time of placement, and the opposite surface is covered with silicone resin or the like and is electrically insulated. That is, leakage of applied electrical energy to tissues and organs around the nerve tissue is reduced.
When the target nerve tissue is a vagus nerve, the peeled nerve tissue often has an outer diameter of about 1 to 2 mm, and the lead core wire and the electrode of the electrode part are φ2 mm or less in order to cope with them. It is preferable to be formed.

The support part 103 is formed by extending a part of the silicone resin covering a part of the electrode part 102 in a substantially arc shape. In consideration of the function of the support portion 103, the arc shape is preferably set so as to have an arc diameter larger than the outer diameter of the nerve tissue. The support part 103 can be elastically deformed, and the electrodes 102A and 102B can be brought into contact with the nerve tissue by sandwiching and supporting the nerve tissue with the electrode part 102. Since the support portion 103 can be deformed along the outer peripheral surface of the electrode portion 102, the entire electrode 100 can be inserted so as to be accommodated in the third lumen 15 as shown in FIG. 3.
The number and shape of the support portions may be appropriately set as long as the purpose of bringing the electrodes 102A and 102B into contact with the nerve tissue is achieved.
The thickness of the support part is preferably 0.5 mm or less so as not to give an excessive load to the target tissue.

  The stylet 40 is made of a resin or metal as a material so that it can be inserted into the inner cavity 104 of the lead portion 101. The tip 40A (see FIG. 5) of the stylet 40 is crushed in the radial direction so as to correspond to the shape of the tip of the lumen 104. Therefore, when the tip 40A is inserted into the tip of the lumen 104 and the stylet 40 is rotated, the electrode 100 can be rotated around the axis of the lead 101. Further, by moving the stylet 40 in the axial direction or pulling the proximal end side of the lead portion 101 toward the hand, the electrode portion 102 can be projected and retracted from the distal end opening of the third lumen 15.

A watertight member such as an O-ring (not shown) is attached to the proximal end side of the second lumen 14 and the third lumen 15, and the peeling portion 30 and the electrode 100 are inserted into the second lumen 14 and the third lumen 15, respectively. Thus, the proximal end sides of the second lumen 14 and the third lumen 15 are kept watertight.
As shown in FIG. 1, the drainage tube 2 is connected to the second lumen 14. A drainage pump 3 is connected to the drainage tube 2, and body fluid and blood that have entered the second lumen 14 from the front end opening of the second lumen 14 can be sucked and discharged out of the lumen. A syringe 4 is connected to the third lumen 15, and by supplying physiological saline (saline) or the like from the syringe 4 into the third lumen 15, the saline is released from the tip opening of the third lumen 15 to cap it. 12 can be washed, and the visual field of the observation unit 20 can be improved.

  The operation at the time of use of the indwelling system 1 configured as described above will be described by taking as an example the case where the electrode 100 is indwelled for the human right vagus nerve (hereinafter simply referred to as “vagus nerve”; target nerve tissue). To do. The vagus nerve is a nerve tissue stimulation site in the vicinity of the heart. is there.

The surgeon inserts the observation part 20 into the first lumen 13 of the introducer 10, and inserts the electrode 100 through which the peeling part 30 and the stylet 40 are inserted into the second lumen 14 and the third lumen 15, respectively. A weak voltage is applied between the discrimination electrodes 18 and 19 by the discrimination power source 5.
The preparation before use of the indwelling system 1 is thus completed, but the peeling part 30 and the electrode 100 are not necessarily inserted at this time, and may be inserted after the introducer 10 reaches the vicinity of the vagus nerve. In this case, it is preferable to plug the base ends of the second lumen 14 and the third lumen 15 as necessary.

Next, the operator forms a small incision (insertion site) on the living body surface of the patient P, and inserts the conical portion 12B of the introducer 10. In this example, as shown in FIG. 7, a small incision is formed near the upper rib cage Ti of the patient P.
After inserting the introducer 10 into the small incision, the surgeon pushes the introducer 10 into the body while holding the main body 11 and applying an axial force while confirming the state around the cap 12 with the observation unit 20. . As shown in FIG. 8, since the upper thorax Ti is near the trachea Tc, when the introducer 10 is inserted, the whitish tubular trachea Tc becomes visible in the field of view of the observation unit 20 in a short time. In this example, the trachea Tc can be used as a guide to the vagus nerve Vn.

In the access path of the indwelling system 1 in this example, since there are many relatively soft loose connective tissues around the introducer 10, by pushing the introducer 10 with the conical portion 12B at the front, The introducer 10 can be advanced by bluntly incising existing living tissue such as loose connective tissue by the conical portion 12B. Therefore, when the introducer 10 is advanced, a large amount of force is not required when the introducer 10 is pushed in to advance. Further, when the introducer 10 is advanced along the trachea Tc, the interface between the trachea Tc and the living tissue around the trachea easily breaks, so that the blunt dissection can be further facilitated. Since the trachea Tc is covered with cartilage, unless the tip of the conical portion 12B is sharp, there is no fear that the trachea Tc will be damaged by the advancement of the introducer 10.
The loose connective tissue that occupies most of the living tissue has few blood vessels, and the conical portion 12B that is not sharp cuts the blood vessels, so there is not much bleeding while the introducer 10 is advanced. However, since the bodily fluid such as interstitial fluid exudes from the bluntly dissected biological tissue, it is aspirated and discharged using the drainage pump 3 as necessary.

  The observation unit 20 inserted into the introduction tool 10 can advance and retreat in the axial direction and can rotate about its own axis. Therefore, the operator can appropriately observe the entire periphery of the cap 12 including the front of the conical portion 12B and the periphery of the cylindrical portion 12A by appropriately operating the observation unit 20 in the first lumen 13. Therefore, the distal end portion of the introducer 10 can be easily advanced to the vicinity of the heart where the vagus nerve Vn exists while confirming the living tissue around the cap 12.

There are cases where the introducer 10 approaches another nerve or the like before reaching the vagus nerve Vn. There are various types of nerves, but they all have white lines that are difficult for an operator to distinguish.
Generally, when an electrical stimulus is applied to a nerve, a biological reaction corresponding to the type of nerve occurs in the patient. For example, it is known that when the vagus nerve is stimulated, the heart rate of the patient decreases, and when the phrenic nerve is stimulated, the periphery of the patient's abdomen is convulsed.
The surgeon can discriminate whether or not the nerve to which the introducer 10 has approached is the vagus nerve Vn by bringing the discriminating electrodes 18 and 19 into contact with the approaching nerve as appropriate and directly observing the biological reaction of the patient P. it can.
If this nerve is the vagus nerve Vn, the nerve is treated as described below. If this nerve is not the vagus nerve Vn, the route for advancing the introducer 10 is changed, and the above procedure is repeated until the vagus nerve Vn is found.

  After confirming the vagus nerve Vn, the operator removes a part of the surrounding tissue so that the electrode 100 can be placed, exposes a part of the vagus nerve Vn, and further peels the part from the surrounding tissue. To do. The surgeon advances the rod 31 of the peeling portion 30 inserted through the second lumen 14 and protrudes from the distal end of the introducer 10. The peripheral tissue on the surface of the vagus nerve Vn is removed by the spatula portion 32 while the introducer 10 is advanced / retracted and rotated as necessary. Since the composition of the surrounding tissue is substantially the same as that of the above-described living tissue, it can be easily removed by the spatula portion 32. Thereafter, as shown in FIG. 9A, by pushing and pulling the rod 31 with the end of the spatula 32 pressed against the vagus nerve Vn, the spatula 32 is advanced and retracted in the axial direction of the rod 31. As shown in FIG. 9B, the vagus nerve Vn can be easily detached from the surrounding tissue St. After the peeling process is completed, the operator stores the peeling portion 30 in the second lumen 14.

When the vagus nerve Vn is removed, the surgeon projects the electrode 100 into which the stylet 40 is inserted from the third lumen 15. While rotating the stylet 40 to adjust the position of the support portion 103, the free end of the support portion 103 is hung on the part where the vagus nerve Vn is peeled off, so that the vagus nerve Vn and the surrounding tissue St are between them. insert. Then, as shown in FIGS. 10 and 11, the vagus nerve Vn is supported between the support portion 103 and the electrode portion 102, and the electrode 100 is connected to the vagus nerve Vn so that the electrode portion 102 and the vagus nerve Vn are in close contact with each other. Detained.
In addition, when a physiological saline solution (saline) is injected and sucked into the space where treatment is performed during the exfoliation treatment with respect to the vagus nerve Vn or when the electrode 100 is indwelled, the visual field of the observation unit 20 may be clarified. it can. Alternatively, a space for treatment may be formed by supplying carbon dioxide gas to the space instead of raw food and pushing away surrounding tissues.

After placement of the electrode 100, the operator removes the stylet 40 from the electrode 100, retracts the introducer 10 and removes it from the body. Since the peripheral tissue and the living tissue were originally arranged without gaps in the access route into which the introducer 10 entered, the route through which the introducer 10 passed with the removal of the introducer 10 was not affected by the surrounding tissues and the living tissue. Buried. Therefore, after the introduction tool 10 is removed, the surrounding tissue and the living tissue are arranged around the placed electrode 100 with almost no gap, and the electrode 100 is positioned at the placement position by the surrounding tissue and the living tissue. For this reason, it is not necessary to perform suturing or the like for fixing after the electrode 100 is placed. In addition, the position of the electrode is likely to be stable in the vicinity of the upper thorax area because there is little movement due to the patient's body movement.
By removing the introduction tool 10, a series of operations for placing the electrode 100 is completed.

  After the placement of the electrode 100, the connector 105 of the electrode 100 is connected to the nerve stimulation device, and treatment by electrical stimulation is started. For example, a rectangular pulse voltage having a width of several tens of microseconds (μsec) to several milliseconds (msec) is applied at a frequency of several tens of hertz (Hz). The voltage value of the rectangular pulse voltage is appropriately set in the range of several volts to several tens of volts. Depending on the treatment content, it is possible to select between continuous stimulation and intermittent stimulation, and the period for performing electrical stimulation is appropriately determined according to the treatment.

  After the treatment is completed, the connector 105 is detached from the nerve stimulation device, and the end of the lead portion 101 is pulled, so that the support portion 103 is detached from the vagus nerve Vn. When pulled further, the electrode 100 can be extracted outside the body through the surrounding tissue and the living tissue. That is, since a relatively invasive surgical procedure is not necessary to remove the electrode 100, the burden on the patient when removing the electrode is greatly reduced.

  The conventional heart treatment device described in Patent Document 1 stimulates the heart and the vagus nerve in response to bradycardia, tachycardia or fibrillation of the heart. Even if this heart treatment apparatus is used, the type of nerve cannot be identified, and there is a possibility that the stimulation given to nerves other than the vagus nerve to be treated increases.

According to the indwelling system 1 and the introducer 10 of the present embodiment, the surgeon blunts the living tissue with the conical portion 12B while confirming the periphery of the cap 12 disposed at the distal end of the introducer 10 with the observation unit 20. Make an incision. At this time, a weak voltage is applied by bringing the discrimination electrodes 18 and 19 into contact with the nerve approached by the introducer 10 as necessary. The surgeon can directly discern whether the nerve to which the voltage is applied is the vagus nerve Vn by directly observing the biological reaction of the patient P at this time. A part of the surrounding tissue St is removed from the vagus nerve Vn by performing an exfoliation treatment on the vagus nerve Vn by the exfoliation unit 30, and the electrode 100 is placed on the vagus nerve Vn.
By identifying the type of nerve in this way, it is possible to suppress stimulation of a nerve that is not a treatment target and to place the electrode 100 on the vagus nerve Vn that is a treatment target.

When the vagus nerve Vn is used as a target tissue, it is shorter and lower than a method of penetrating the pleura with a trocar or the like and accessing from the thoracic cavity, or a method of incising a blood vessel and placing an electrode on the blood vessel wall. While the electrode is placed in an invasive manner, the electrical stimulation treatment can be efficiently performed by directly contacting the vagus nerve Vn with the electrode.
The discrimination electrodes 18 and 19 are formed over the entire circumference of the main body 11. For this reason, even if the nerve is located in any direction around the axis of the main body 11 with respect to the main body 11, it is not necessary to rotate the main body 11 around the axis, and the discrimination electrodes 18 and 19 are attached to the nerve. Can be easily contacted.

In addition, the introducer 10 of this embodiment can change the structure variously so that it may demonstrate below.
For example, like the introduction tool 10 </ b> A shown in FIG. 12, the discrimination electrodes 18 </ b> A and 19 </ b> A may be formed only in a partial range in the circumferential direction of the main body 11 on the outer surface of the distal end portion of the main body 11. In this case, the indicator portion may be formed at the same position as the determination electrodes 18A and 19A in the circumferential direction of the first lumen 13.
The indicator portion may be an indicator portion 11 </ b> A provided on the outer surface of the base end portion of the main body 11 or an indicator portion 12 </ b> C provided on the outer surface of the cap 12.

By configuring the discrimination electrodes 18A and 19A of the introducer 10A in this way, it is possible to easily apply a voltage only to specific nerves in the circumferential direction of the main body 11.
In the case where the strength against twisting of the main body 11 is high, by providing the main body 11 with the index portion 11A, the surgeon does not look directly at the determination electrodes 18A and 19A, but the circumferential direction in which the determination electrodes 18A and 19A are formed. The position of is understood. Then, by rotating the introducer 10A about its own axis, the circumferential position where the discrimination electrodes 18A and 19A are formed can be changed.
On the other hand, by providing the indicator 12C on the cap 12, even when the strength against twisting of the main body 11 is low, the discrimination electrodes 18A and 19A are formed by observing the position of the observation unit 20 with the observation unit 20. You can see the position in the circumferential direction.

As in the introduction tool 10 </ b> B shown in FIG. 13, the discrimination electrodes 18 </ b> B and 19 </ b> B may be formed on the outer surface of the distal end portion of the main body 11 so as to extend in the longitudinal direction of the main body 11.
By configuring the discrimination electrodes 18B and 19B of the introducer 10B in this way, the discrimination electrodes 18B and 19B can be easily brought into contact with the nerve in the longitudinal direction of the main body 11, and the detection range of the nerve can be increased.

Further, the discrimination electrodes 18C and 19C may be formed on the outer surface of the cap 12 as in the introduction tool 10C shown in FIG.
By configuring the discrimination electrodes 18C and 19C of the introducer 10C in this way, the state in which the nerve is in contact with the discrimination electrodes 18C and 19C is observed by the observation unit 20 inserted through the first lumen 13 of the introducer 10C. can do.

In addition, the indwelling system 1 of this embodiment can use only the introduction tool 10 of the indwelling system 1 with a general endoscope.
Specifically, the insertion portion of the endoscope is inserted into the first lumen 13 of the introducer 10, and the introducer 10 is inserted through a small incision formed in the patient P while confirming the surrounding state with the endoscope. To go. At this time, when the introduction tool 10 approaches a certain nerve, the surgeon directly observes the biological reaction of the patient P by bringing the discrimination electrodes 18 and 19 of the introduction tool 10 into contact with the nerve as necessary. This identifies whether the nerve is a vagus nerve Vn.
In this way, by directly observing the biological reaction of the patient P using the introducer 10, the type of nerve in contact with the discrimination electrodes 18 and 19 can be easily identified and the procedure can be performed quickly.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. 15, but the same parts as those of the above-described embodiment will be denoted by the same reference numerals, the description thereof will be omitted, and only different points will be described.
As shown in FIG. 15, the indwelling system 7 of this embodiment measures the electrical activity state in the heart Ht of the patient P instead of the monitor 24 of the indwelling system 1 of the first embodiment, and an electrocardiogram (measurement). Result) An electrocardiogram measuring device (monitoring unit) 51 for displaying D1 is provided.
An electrocardiogram measuring instrument 51 having a known configuration can be used, and the electrocardiogram measuring instrument 51 includes a display unit 52 and an electrocardiogram electrode 53.
The electrocardiogram electrode 53 is attached to the living body surface near the heart Ht of the patient P. The potential difference of the predetermined part of the heart Ht detected by the electrocardiogram electrode 53 is transmitted to the processing device (not shown) via the lead wire 54 and processed, and the above-mentioned electrocardiogram D1 is displayed on the display unit 52.
In this example, an image acquired by the observation optical system 21 of the observation unit 20 is also displayed on the display unit 52.

The operation of the indwelling system 7 configured in this way is as follows. After the operator brings the discrimination electrodes 18 and 19 into contact with the nerve of the patient P, the biological reaction of the patient P is directly observed and the electrocardiogram D1 is confirmed. Only the operation is different from the operation described in the first embodiment.
That is, when the discrimination electrodes 18 and 19 of the introducer 10 come into contact with the vagus nerve Vn and a weak voltage is applied to the vagus nerve Vn, the RR interval in the electrocardiogram D1 becomes longer or the heart rate decreases. On the other hand, when a voltage is applied to the sympathetic nerve, the RR interval is shortened or the heart rate is increased.
Thus, not only visually checking the biological reaction of the patient P but also checking the electrocardiogram D1, it is possible to more reliably identify the type of nerve with which the discrimination electrodes 18 and 19 are in contact.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG. 16, but the same portions as those of the above-described embodiment will be denoted by the same reference numerals, the description thereof will be omitted, and only different points will be described.
As shown in FIG. 16, the indwelling system 8 of this embodiment measures the electrical activity state in the motor nerve of the patient P instead of the monitor 24 of the indwelling system 1 of the first embodiment, and the electromyogram. (Measurement result) An electromyogram measuring device (monitoring unit) 61 for displaying D2 is provided.
A known configuration can be used as the electromyogram measuring device 61, and the electromyogram measuring device 61 includes a display unit 62 and an electromyogram electrode 63.
The electromyogram electrode 63 is attached to the abdomen Ab of the patient P. The potential difference of the predetermined part of the abdomen Ab detected by the electromyogram electrode 63 is transmitted to the processing device (not shown) via the lead wire 54 and processed, and the above-mentioned electromyogram D2 is displayed on the display unit 62. The

The operation of the indwelling system 8 configured in this way is as follows. After the surgeon contacts the discrimination electrodes 18 and 19 with the nerve of the patient P, the biological reaction of the patient P is directly observed and the electromyogram D2 is used. The only difference is that the operation described in the first embodiment is confirmed.
That is, when the discrimination electrodes 18 and 19 of the introducer 10 come into contact with the motor nerve and a weak voltage is applied to the motor nerve, the muscle fiber corresponding to the motor nerve is excited. The amplitude at D2 increases.
There are cases where the introducer 10 inserted into the body of the patient P crosses another nerve or the like before reaching the vagus nerve Vn. Nerves are white, and even endoscopically, it is often not clear whether nerves or fat are distinguished. Even in such a case, when the nerve is a motor nerve, the motor nerve can be reliably identified by using the indwelling system 8.
And when the nerve which contacted the discrimination electrodes 18 and 19 was a motor nerve, the route which advances the introduction tool 10 is changed, and the above-mentioned procedure is repeated until the vagus nerve Vn is found.

The first to third embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and the configuration does not depart from the gist of the present invention. Changes are also included. Furthermore, it goes without saying that the configurations shown in the embodiments can be used in appropriate combinations.
For example, in the first to third embodiments, the example in which the introduction tool has three lumens of the first and second lumens and the third lumen that is the electrode lumen has been described. There is no limit to the number of lumens, and any number is possible.
In the first to third embodiments, the introduction tool has a pair of discrimination electrodes, but the number of discrimination electrodes of the introduction tool can be set as appropriate.

Moreover, in the said 2nd Embodiment and 3rd Embodiment, you may use the measuring device which measures the blood glucose level of the patient P continuously as a monitoring part.
When a weak voltage is applied to the vagus nerve Vn, insulin secretion increases and the blood glucose level decreases. By measuring the change in blood glucose level over time in the patient P, it is possible to identify whether the nerve to which the voltage is applied is the vagus nerve Vn.

Furthermore, the present invention includes the following technical ideas.
(Additional item 1)
A cylindrical main body having a lumen; and an incision member having a blunt incision capable of blunt dissection of biological tissue and having transparency and attached to the distal end of the main body An approach method for approaching a target nerve tissue located in the chest using an introducer,
Incising the chest to form the insertion site for the introducer,
Inserting the blunt incision of the introducer into the insertion site;
In the blunt incision part in which the observation part is inserted in the main body, the introduction tool is advanced by bluntly dissecting surrounding tissue while observing the periphery of the incision member,
A voltage is applied to the nerve tissue with the discrimination electrode, and the type of the nerve tissue is identified by observing a biological reaction,
The incision member is moved to the vicinity of the target nerve tissue.

(Appendix 2)
The approach method according to attachment 1, wherein the insertion site is formed in the upper thorax.
(Additional Item 3)
The approach method according to appendix 1, wherein a biological reaction is observed and an electrocardiogram is confirmed.
(Appendix 4)
The approach method according to attachment 1, wherein a biological reaction is observed and an electromyogram is confirmed.

1, 7, 8 Indwelling system (neural stimulation electrode indwelling system)
10, 10A, 10B, 10C Introducing tool 11 Main body 11A, 12C Indicator part 12 Cap (cutting member)
12B Cone (blunt incision)
13 First lumen (first lumen)
14 Second lumen (second lumen)
15 Third lumen (electrode lumen)
18, 18A, 18B, 18C, 19, 19A, 19B, 19C Discrimination electrode 20 Observation unit 30 Peeling unit 51 ECG measuring device (monitoring unit)
61 EMG measuring device (monitoring part)
D1 ECG (measurement result)
D2 Electromyogram (measurement result)

Claims (9)

An introducer for introducing a nerve stimulation electrode into a target nerve tissue,
A cylindrical body having a lumen;
An incision member having a blunt incision for blunt dissection of biological tissue, formed to have transparency, and attached to the tip of the main body;
A discriminating electrode provided on at least one of the outer surface of the distal end portion of the main body and the outer surface of the incising member, and for identifying whether or not the contacted nerve tissue is the target nerve tissue ;
An introduction device comprising:   The introducer according to claim 1, wherein the discrimination electrode is formed over the entire circumference of the main body.   The introducer according to claim 1, wherein the discrimination electrode is formed only in a partial range in the circumferential direction of the main body. At least one of the proximal end portion of the main body and the cutting member is formed with an index portion indicating a circumferential position where the discrimination electrode is formed at the same position as the discrimination electrode in the circumferential direction of the lumen. The introducer according to claim 3, wherein the introducer is provided.   The introducer according to claim 1, wherein the discrimination electrode is formed to extend in a longitudinal direction of the main body. A nerve stimulation electrode placement system for placing a nerve stimulation electrode in a desired target nerve tissue,
An introducer according to claim 1;
An observation part that is inserted into the introducer so that the periphery of the incision member can be observed through the incision member;
A peeling section that is arranged to be rotatable about its own axis with respect to the introducer and to be relatively movable in the axial direction, and removes surrounding tissue around the target nerve tissue;
A nerve stimulation electrode placement system comprising:   The nerve stimulation electrode placement system according to claim 6, further comprising a monitoring unit that measures a state of the living body and displays the measurement result.   The nerve stimulation electrode placement system according to claim 7, wherein the measurement result is an electrocardiogram.   The nerve stimulation electrode placement system according to claim 7, wherein the measurement result is an electromyogram.

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