JP2017000230A - Electrode device for spinal code monitoring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode device for spinal cord monitoring capable of easily and directly stimulating a spinal cord electrically in a noninvasive manner.SOLUTION: The electrode device for spinal cord monitoring includes: a long member 10 capable of being inserted into an esophagus and having flexibility; a first electrode 20 arranged on an outer peripheral face of the long member 10 in a predetermined range equal to or smaller than a half periphery in the peripheral direction of the long member 10 and capable of contacting an inner peripheral face of the esophagus; a second electrode 23 arranged at a position shifted parallely in a center line X1 direction of the long member 10 with respect to the first electrode 20 on the outer peripheral face of the long member 10 and capable of contacting the inner peripheral face of the esophagus together with the first electrode 20; and a control section 40 generating a signal for stimulating a spinal cord electrically through the esophagus and capable of being connected to the first electrode 20 and the second electrode 23 for outputting a signal to the first electrode 20 and the second electrode 23 individually.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an electrode device for spinal cord function monitoring.

  Various evoked potentials are used to monitor spinal cord function during surgery. In particular, for monitoring ischemic spinal cord injury during aortic surgery, motor-evoked potentials (see, for example, Non-Patent Document 1), somatosensory evoked potentials (for example, see Non-Patent Document 2), spinal cord-evoked potentials (for example, Non-Patent Documents) 3) has been used.

  Motor evoked potentials using electrocranial electrosurgery for transcranial electrical stimulation have been frequently used because they reflect the function of the motor nerve transmission pathway, high sensitivity to ischemia, short reaction time, and simplicity of the procedure. . However, transcranial electrical stimulation has limitations in terms of proper placement and fixation of electrodes, possible stimulation intensity, etc. in addition to the principle weakness of being easily affected by anesthetics. For this reason, low specificity due to natural fluctuations in potential is a problem.

  On the other hand, somatosensory evoked potentials are simple, but they reflect the function of sensory nerve transmission pathways, so both sensitivity and specificity to ischemia are low, and the response time to ischemia is long, so the frequency of use is reduced. ing.

  Spinal cord evoked potential is a method in which the spinal cord is directly electrically stimulated using two epidural electrodes and the potential induced in the spinal cord is recorded. This has the advantage of not being affected by anesthetics because it is not mediated by synapses, but it does not reflect the function of anterior horn cells with the lowest ischemic tolerance. long.

Japanese Patent No. 2799199 Japanese Patent No. 5295119

de Haan P, Kalkman CJ, de Mol BA, Ubags LH, Veldman DJ, Jacobs MJ.Efficacy of transcranial motor-evoked myogenic potentials to detect spinal cord ischemia during operations for thoracoabdominal aneurysms.J Thorac Cardiovasc Surg 1997; 113: 87-100 . Laschinger JC, Cunningham JN, Jr., Baumann FG, Cooper MM, Krieger KH, Spencer FC.Monitoring of somatosensory evoked potentials during surgical procedures on the thoracoabdominal aorta.III.Intraoperative identification of vessels critical to spinal cord blood supply.J Thorac Cardiovasc Surg 1987; 94: 271-4. Shiiya N, Yasuda K, Matsui Y, Sakuma M, Sasaki S. Spinal cord protection during thoracoabdominal aortic aneurysm repair: results of selective reconstruction of the critical segmental arteries guided by evoked spinal cord potential monitoring.J Vasc Surg 1995; 21: 970- Five

Since aortic surgery uses anticoagulants during surgery, there is a risk of epidural hematoma formation when using epidural electrodes to electrically stimulate the spinal cord. For this reason, the opportunity for spinal cord stimulation using epidural electrodes to be used clinically has been drastically reduced.
In order to stimulate non-invasively or perform electrical measurement on tissues in the body, for example, medical instruments that are inserted into the esophagus as disclosed in Patent Documents 1 and 2 are known. The techniques disclosed in Patent Literatures 1 and 2 do not consider effective electrical stimulation of the spinal cord.
The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a spinal cord function monitoring electrode device capable of directly and directly stimulating the spinal cord non-invasively.

  One aspect of the present invention is a flexible long member that can be inserted into the esophagus, and an outer peripheral surface of the long member that is arranged within a predetermined range of a half circumference or less in the circumferential direction of the long member. A first electrode capable of contacting an inner peripheral surface, and provided on the outer peripheral surface of the long member at a position shifted in parallel to the center line direction of the long member with respect to the first electrode, together with the first electrode A second electrode that can contact the inner peripheral surface of the esophagus, a first lead connected to the first electrode that can be connected to a control unit that generates a signal for electrical stimulation of the spinal cord, and a connection to the control unit A spinal cord function monitoring electrode device comprising: a second lead that is capable of being insulated from the first lead and connected to the second electrode.

  The said aspect WHEREIN: The said elongate member may consist of the cylindrical member which has an opening in a front-end | tip and a base end.

  The electrode device for monitoring spinal cord function according to the above aspect is provided at a position further displaced in parallel to the center line direction of the long member with respect to the first electrode and the second electrode on the outer peripheral surface of the long member. You may further provide the 3rd electrode which can contact the inner peripheral surface of the said esophagus with a 1st electrode and a said 2nd electrode.

  ADVANTAGE OF THE INVENTION According to this invention, the electrode apparatus for spinal cord function monitoring which can carry out electrical stimulation of the spinal cord directly non-invasively and easily can be provided.

It is a typical top view which shows the electrode apparatus for spinal cord function monitoring of one Embodiment of this invention. It is typical sectional drawing in the AA of FIG. It is typical sectional drawing in the BB line of FIG. It is a schematic diagram which shows the other structural example of the 1st electrode in the electrode apparatus for spinal cord function monitoring. It is a figure for demonstrating an effect | action of the electrode apparatus for spinal cord function monitoring. It is a figure which shows the structure of the modification of the embodiment.

  An embodiment of the present invention will be described. FIG. 1 is a schematic plan view showing an electrode device for spinal cord function monitoring according to the present embodiment. FIG. 2 is a schematic cross-sectional view taken along line AA in FIG. 3 is a schematic cross-sectional view taken along line BB in FIG. FIG. 4 is a schematic diagram showing another configuration example of the first electrode in the spinal function monitoring electrode device of the present embodiment. FIG. 5 is a diagram for explaining the operation of the spinal cord function monitoring electrode device.

  A spinal cord function monitoring electrode device 1 (hereinafter, simply referred to as “electrode device 1”) of the present embodiment shown in FIG. 1 includes a long member 10, a first electrode 20, a second electrode 23, and a lead portion. 30.

The long member 10 shown in FIGS. 1 to 3 is a flexible member that can be inserted from the mouth into the esophagus, for example. The material of the long member 10 is flexible to the extent that the digestive tract or the like is not damaged, and the part inside the body corresponds to the operation by the operation outside the body in a state where a part of the long member 10 is arranged in the digestive tract. It is preferable that the material has such a hardness that it can be operated. The material of the long member 10 is not particularly limited as long as the material has biocompatibility.
The elongate member 10 of this embodiment has the front-end | tip 11 distribute | arranged in an esophagus at the time of use of the electrode apparatus 1, and the base end 12 distribute | arranged to the other side. The long member 10 has a cylindrical shape having openings at the distal end 11 and the proximal end 12. A known medical instrument such as an ultrasonic diagnostic probe P can be inserted into the long member 10 formed in a cylindrical shape. In addition, it is not essential that the long member 10 is cylindrical.
A first recess 14 that holds the first electrode 20 and a second recess 17 that holds the second electrode 23 are formed on the outer peripheral surface 13 in the vicinity of the tip 11 of the long member 10.

A long linear marker 13 a is provided on the outer peripheral surface 13 of the long member 10 in parallel with the center line X <b> 1 of the long member 10. Since the marker 13a is linearly provided on the outer peripheral surface 13 of the long member 10, the first electrode 20 in the esophagus is inserted when the distal end 11 side of the long member 10 is inserted into the esophagus from the mouth. And the direction of the 2nd electrode 23 can be grasped | ascertained by seeing the marker 13a visually recognizable in the base end 12 side which has come out of the body. In the present embodiment, the marker 13 a is configured by a single line that passes through the first recess 14 and the second recess 17 and extends in parallel with the center line X <b> 1 of the long member 10.
Further, the marker 13 a may have a scale that gradually increases from the distal end 11 of the long member 10 to the base end 12 side as an origin, and may be used as an index of the insertion amount of the long member 10. .

The first recess 14 holds the first electrode 20 at a position where the first electrode 20 is flush with the outer peripheral surface 13 of the long member 10. That is, in the present embodiment, the first electrode 20 is embedded in the first recess 14 in a state where the first electrode 20 is exposed on the outer peripheral surface 13 of the long member 10. In addition, the 1st recessed part 14 may hold | maintain the 1st electrode 20 in the state in which the 1st electrode 20 protruded slightly with respect to the outer peripheral surface 13 of the elongate member 10. FIG.
The bottom surface 15 of the first recess 14 may communicate with the internal space of the long member 10. In other words, the first recess 14 may have a passage that penetrates the side wall of the tubular long member 10. A lead portion 30 connected to the first electrode 20 is inserted into the passage provided in the bottom surface 15 of the first recess 14. It is not essential that a passage is provided in the first recess 14.

The second concave portion 17 is provided at a position further away from the first concave portion 14 toward the base end 12 side of the long member 10. The second recess 17 is located at a position where the first recess 14 is translated along the center line X <b> 1 of the long member 10 toward the base end 12 side of the long member 10. The second recess 17 holds the second electrode 23 at a position where the second electrode 23 is flush with the outer peripheral surface 13 of the long member 10. That is, in the present embodiment, the second electrode 23 is embedded in the second recess 17 in a state where the second electrode 23 is exposed on the outer peripheral surface 13 of the long member 10. Note that the second recess 17 may hold the second electrode 23 in a state where the second electrode 23 slightly protrudes from the outer peripheral surface 13 of the long member 10.
The bottom surface (not shown) of the second recess 17 may communicate with the internal space of the elongated member 10 as with the first recess 14.

The first electrode 20 is fixed in the first recess 14 of the long member 10. The first electrode 20 has, for example, a columnar shape or a disk shape, and the first end surface 21 which is one of both end surfaces in the center line direction of the first electrode 20 can contact the esophageal tissue. The shape of the first electrode 20 is not particularly limited.
The first end surface 21 of the first electrode 20 is directed in a direction orthogonal to the center line X <b> 1 of the long member 10 (outside in the radial direction of the long member 10). The first end surface 21 of the first electrode 20 may have a curved shape that follows the outer peripheral surface 13 of the long member 10. Further, the boundary portion 22 between the outer peripheral surface of the first electrode 20 and the first end surface 21 of the first electrode 20 may be rounded. By having these structures, even if the first electrode 20 slides on the esophageal tissue in contact with the esophageal tissue, the tissue is hardly damaged.
Note that the first end surface 21 of the first electrode 20 may be located slightly shifted to the inner side of the long member 10 from the outer peripheral surface 13 of the long member 10. In this case, the first electrode 20 and the inner surface of the esophagus are electrically connected via body fluid or the like.
The material of the first electrode 20 may be a conductor having biocompatibility. For example, examples of the material of the first electrode 20 include stainless steel and platinum.

The second electrode 23 is fixed in the second recess 17 of the long member 10. The shape of the second electrode 23 is not particularly limited. For example, the second electrode 23 of the present embodiment is the same shape and size as the first electrode 20. Like the first electrode 20, the second end face 24, which is one of both end faces in the center line direction of the second electrode 23, can contact the esophageal tissue. The second end surface 24 of the second electrode 23 is a surface substantially parallel to the first end surface 21 of the first electrode 20.
The material of the second electrode 23 may be a biocompatible conductor. The material of the second electrode 23 may be the same as the material of the first electrode 20 or may be different from the material of the first electrode 20.

  In addition, the shape of the 1st electrode 20 and the 2nd electrode 23 is not restricted to the above-mentioned column shape or disk shape. For example, as shown in FIG. 4, in place of the first electrode 20 of the present embodiment, a first arc-shaped curved surface 25 that is long in the circumferential direction of the long member 10 along the outer peripheral surface 13 of the long member 10. One electrode 20A may be provided. Although not shown, instead of the second electrode 23, a second electrode having an arcuate curved surface that is long in the circumferential direction of the long member 10 may be provided along the outer peripheral surface 13 of the long member 10.

  As shown in FIG. 2 or FIG. 4, if the first electrode 20 (20 </ b> A) and the second electrode 23 are provided in a region of a half circumference or less in the circumferential direction on the outer peripheral surface 13 of the long member 10. When the first electrode 20 (20A) and the second electrode 23 are turned to the back side in the esophagus by the operation of rotating the long member 10 about the center line X1 of the long member 10, the belly side The first electrode 20 (20A) and the second electrode 23 may not be directed. As a result, when the first electrode 20 (20A) and the second electrode 23 are provided in an area of the outer circumferential surface 13 of the long member 10 in a circumferential direction equal to or less than a half circumference, The 1st electrode 20 (20A) and the 2nd electrode 23 can be arrange | positioned in the position which can perform electrical stimulation specifically with respect to the back | stimulation target tissue (this embodiment spinal cord).

The lead part 30 connects the first lead 31 connected to the first electrode 20, the second lead 32 connected to the second electrode 23, and the first lead 31 and the second lead 32 to the control part 40 described later. And a connector 33. The lead portion 30 of the present embodiment is connected to the first electrode 20 and the second electrode 23 inside the long member 10 and extends to the proximal end 12 side of the long member 10 through the internal space of the long member 10. The long member 10 extends from the opening of the proximal end 12 to the outside of the long member 10.
The first lead 31 and the second lead 32 can be connected to a control unit 40 described later via a connector 33. Further, the first lead 31 and the second lead 32 are electrically insulated from each other. Specific configurations of the first lead 31 and the second lead 32 are not particularly limited. For example, the first lead 31 and the second lead 32 may have a core wire made of a conductor for transmitting an electrical signal generated by the control unit 40 and an insulating film covering the core wire.

Next, an example of a control unit that can be attached to the electrode device 1 when the electrode device 1 of the present embodiment is used will be described.
The control unit 40 generates a predetermined signal suitable for electrical stimulation of the spinal cord, and outputs the predetermined signal to the first electrode 20 and the second electrode 23 via the lead unit 30.
The predetermined signal output from the control unit 40 is not particularly limited as long as the signal is suitable for electrical stimulation of the spinal cord. For example, the control unit 40 of the present embodiment generates a pulse signal that continues for 0.05 ms at a constant voltage in the range of 100 V or more and 600 V or less as a signal for stimulating the spinal cord through the esophagus 5 times every 2 ms. The electrical stimulation of the spinal cord via the esophagus in the present embodiment can induce a potential that is as good as or better than that of the transcranial brain electrical stimulation, even if the signal has a lower stimulation intensity than the transcranial brain electrical stimulation.

The operation of the electrode device 1 of the present embodiment will be described. FIG. 5 is an explanatory view schematically showing a process of inserting the electrode device 1 of the present embodiment from the mouth into the esophagus.
The electrode device 1 is used together with an evoked potential inspection device that records an evoked potential generated by electrical stimulation of the spinal cord.

  When the electrode device 1 is used, the long member 10 is inserted from the mouth into the esophagus as shown in FIG. The first electrode 20 and the second electrode 23 on the distal end 11 side of the long member 10 inserted into the esophagus are not directly visible from outside the body, but are markers that extend in parallel with the center line X1 of the long member 10 It can be easily grasped based on the position of 13a (see FIG. 1).

  As shown in FIG. 5, in a state where the long member 10 is inserted into the esophagus, the inner peripheral surface of the esophagus is substantially in close contact with the outer surface of the long member 10, and the first electrode 20 and the second electrode 23 are Both are in contact with the inner surface of the esophagus. After the long member 10 is inserted into the esophagus, the user of the electrode device 1 rotates the long member 10 in the circumferential direction so that the first electrode 20 and the second electrode 23 face the spinal cord side.

  In a state where the first electrode 20 and the second electrode 23 are directed toward the spinal cord side, a user or the like of the electrode device 1 operates the control unit 40 to perform a predetermined operation on the first electrode 20 and the second electrode 23. Output a signal. The spinal cord is electrically stimulated through the esophagus by signals output from the control unit 40 to the first electrode 20 and the second electrode 23. The evoked potential in the electrified spinal cord is detected and recorded by an evoked potential testing device.

In this embodiment, since the spinal cord is electrically stimulated via the esophagus using the electrode that contacts the inner surface of the esophagus, the invasion when arranging the electrode for stimulating the spinal cord is extremely low. In addition, the voltage required for spinal cord stimulation may be lower than the voltage required for transcranial brain electrical stimulation, so that the esophagus is less likely to burn.
Moreover, the position of the 1st electrode 20 and the 2nd electrode 23 in the electrode apparatus 1 of this embodiment can be easily changed by rotating the base end 12 part of the elongate member 10 outside a body, and after positioning The first electrode 20 and the second electrode 23 are not easily displaced by the frictional force caused by the long member 10 being in contact with the inner surface of the esophagus. For this reason, arrangement | positioning of the electrode for the electrical stimulation with respect to a spinal cord is easy.
Thus, according to the electrode device 1 of the present embodiment, the spinal cord can be directly electrically stimulated noninvasively and easily.

  Furthermore, since the electrode device 1 of the present embodiment can electrically stimulate the spinal cord with the first electrode 20 and the second electrode 23 that come into contact with the esophagus, both the esophagus and the body surface are sandwiched between the spinal cords. As compared with the case where the electrode is connected to the electrode, the attachment of the electrode is simple.

(Modification)
A modification of the above embodiment will be described. FIG. 6 is a cross-sectional view showing an electrode device of this modification.
The electrode device 1 of the present modification further includes a third electrode 26 in addition to the first electrode 20 and the second electrode 23 disclosed in the above embodiment.

  The third electrode 26 is disposed at a position separated from the first electrode 20 and the second electrode 23 in the direction of the center line X1 of the long member 10. For example, the third electrode 26 is embedded in a third recess 27 formed at a position separated from the first recess 14 and the second recess 17 in the direction of the center line X1 of the long member 10. The 3rd recessed part 27 is opened by the outer peripheral surface 13 of the elongate member 10 similarly to the 1st recessed part 14 and the 2nd recessed part 17 which were disclosed by the said embodiment, and a part of 3rd electrode 26 can contact an esophagus inner surface. The third electrode 26 is held with a part of the third electrode 26 exposed so that

  Moreover, the lead part 30 disclosed in the above embodiment is attached to the third electrode 26 in order to connect the third electrode 26 and the control part 40 (see FIG. 1).

  In this modification, two electrodes can be arbitrarily selected from the first electrode 20, the second electrode 23, and the third electrode 26 to serve as an anode and a cathode.

  As a result, after the positioning of the first electrode 20, the second electrode 23, and the third electrode 26 with respect to the esophagus, there are options for the position and range for electrical stimulation. That is, when using the 1st electrode 20 and the 2nd electrode 23 like the said embodiment, unlike the said embodiment, when using the 2nd electrode 23 and the 3rd electrode 26, the 1st electrode 20 and the 3rd electrode are used. In the case of using the electrode 26, a suitable combination can be selected from a plurality of options and used.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
For example, although the example provided with a total of three electrodes, the 1st electrode 20, the 2nd electrode 23, and the 3rd electrode 26, is shown in the modification of the said embodiment, the number of electrodes may be more than three. .
Further, these electrodes are not necessarily arranged in a line in the direction of the center line X1 of the long member 10. That is, a plurality of electrodes separated from each other may be selected from a large number of electrodes.
Moreover, a spinal cord monitoring system may be configured by combining the spinal cord function monitoring electrode device disclosed in the above embodiment and its control unit.

DESCRIPTION OF SYMBOLS 1 Electrode apparatus for spinal cord function monitoring 10 Long member 11 Tip 12 Base end 13 Outer peripheral surface 13a Marker 14 First recessed part 15 Bottom face 17 Second recessed part 20 First electrode 21 First end face 22 Boundary part 23 Second electrode 24 Second end face 25 Curved surface 26 Third electrode 27 Third recess 30 Lead part 31 First lead 32 Second lead 33 Connector 40 Control part

Claims (3)

A flexible long member that can be inserted into the esophagus;
A first electrode arranged in a predetermined range of a half circumference or less in the circumferential direction of the long member on the outer peripheral surface of the long member and capable of contacting the inner peripheral surface of the esophagus;
A second electrode provided on the outer peripheral surface of the elongate member at a position shifted in parallel to the center line direction of the elongate member with respect to the first electrode and capable of contacting the inner peripheral surface of the esophagus together with the first electrode When,
A first lead connected to the first electrode and connectable to a controller that generates a signal for electrical stimulation of the spinal cord;
A second lead connected to the second electrode in a state that is connectable to the control unit and insulated from the first lead;
An electrode device for spinal cord function monitoring.   The electrode device for monitoring spinal cord function according to claim 1, wherein the long member is formed of a cylindrical member having openings at a distal end and a proximal end. The esophagus is provided along the first electrode and the second electrode on the outer circumferential surface of the long member at a position shifted further in parallel with the first electrode and the second electrode in the direction of the center line of the long member. A third electrode capable of contacting the inner peripheral surface of
The electrode device for monitoring spinal cord function according to claim 1.

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