Method for operating a neurological examination device and neurological examination device

Abstract

To provide an inspection method and an inspection device which can inspect a nerve around a rectum and a tissue other than the nerve in a distinguished manner.SOLUTION: An inspection method comprises: a step 1 of applying low-frequency electric stimulation to a nerve near a rectum-unique fascia 2 wrapping a rectum 1 or a tissue other than the nerve; a step 2 of making a distortion sensor 21 that detects the shape change of a balloon 11 inserted to a urinary tract 50 detect a contraction reaction of an inner urethral muscle 51; and a step 3 of determining that the object applied with the low-frequency electric stimulation is the nerve when the contraction reaction of the inner urethral muscle 51 is detected in a case where the low-frequency electric stimulation is applied to the nerve or the tissue other than the nerve, and determining that the object applied with the low-frequency electric stimulation is the tissue other than the nerve when the contraction reaction of the inner urethral muscle 51 is not detected.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a nerve examination method for examining nerves adjacent to the fascia propria of the rectum, and a nerve examination device used for the examination. [Background technology]

[0002] Surgery for rectal cancer will be explained based on Non-Patent Document 1. In surgery for rectal cancer, it is important to achieve both radical cure and functional preservation. FIG. 1 (a partially exaggerated version of FIG. 1 in Non-Patent Document 1) shows a cross-sectional view of the rectum and its surrounding tissues. The rectum 1 is surrounded by the fascia recti proper 2, a thin membrane that encases the fat of the mesorectum. The Denonvilliers' fascia (DVF) 3 is located on the outer periphery of the fascia recti proper 2. The outside of the DVF 3 is divided into multiple membranes. The prehypogastric fascia 5 is located between the hypogastric nerve and the fascia recti proper 2. The prehypogastric fascia 5 lines the fascia recti proper 2, covers the ventral side of the hypogastric nerve, and further forms the boundary between the pelvic plexus and the fascia recti proper 2, continuing to the outside of the DVF 3. On the left side of the DVF 3 in the figure, there is a nerve plexus 4, a collection of nerves, a part of which, as the hypogastric nerve 6, is located below the DVF 3.

[0003] The landmarks for nerve-sparing dissection layers are DVF3 and the prehypogastric fascia 5. DVF3 on the anterior wall and the prehypogastric fascia 5 are continuous layers, and dissection on the inside of these layers allows for surgery that preserves the autonomic nerves while they are covered by the membrane. The layer to be dissected must be selected depending on the progression of the tumor, but it is important to always be aware during surgery of whether the dissection is being performed in the prehypogastric fascia 5 or in front of or behind DVF3, in order to prevent nerve damage. Thus, in conventional rectal cancer removal surgery, when performing a dissection midway between the DVF 3 and the hypogastric preneurial fascia 5, the dissection location must be determined through experience, and it has been difficult for inexperienced surgeons to perform the dissection without damaging the nerves.

[0004] Therefore, there is a strong demand for the development of an examination method that can distinguish between nerves and fascia. Regarding nerve testing methods, Non-Patent Document 2 describes the recent widespread use of an insertion tube with a surface electrode to prevent recurrent laryngeal nerve damage during thyroid and parathyroid surgery. The document describes a testing method in which a stimulation electrode is brought into contact with tissue, electrical stimulation is applied, and vocal cord muscle activity is monitored to distinguish between nerves and non-nerve tissues. The present inventors are conducting research in the hope of establishing such a method in rectal cancer surgery as well.

[0005] Non-patent document 3 reports that in an experiment using female mongrel dogs, electrical stimulation of the hypogastric nerve caused a change in the intraurethral pressure response waveform. 2, a tube 102 having a balloon 103 near its tip is inserted into and attached to a urethra 101, which is used to excrete urine from a bladder 100. Air is then injected into the balloon 103 at a predetermined pressure to inflate the balloon 103 and block the urethra. Meanwhile, a first electrode 104 is connected to the hypogastric nerve and a second electrode 105 is connected to the pudendal nerve on both sides of the balloon. When a low-frequency current is applied by the first electrode 104 or the second electrode 105 to electrically stimulate the pudendal nerve or the hypogastric nerve, the urethral muscles contract, compressing the balloon 103 and increasing the air pressure inside the balloon 103. The change in air pressure is measured by a pressure gauge. Figure 3 shows experimental results when electrical stimulation was applied to the hypogastric nerve, for example. In (A), a low-frequency current of 2 Hz was applied, in (B), a low-frequency current of 4 Hz was applied, in (C), a low-frequency current of 8 Hz was applied, and in (D), a low-frequency current of 10 Hz was applied. The graph shows the change in the internal pressure of each balloon 103. The vertical axis of the graph is divided into 10 mH2O divisions. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] Yusuke Kinugasa, Clinical Anatomy Research Meeting Record No. 13, February 2013 "Fascia anatomy around the rectum from a surgeon's perspective and the peeling layer for function-preserving rectal cancer surgery" [Non-patent document 2] Yukihito Araki, Akihiro Shioya, Journal of Otorhinolaryngology, Vol. 85, No. 8, July 2013, "Intraoperative Recurrent Laryngeal Nerve Monitoring" [Non-patent document 3] Takashi Shiotani, Journal of the Japanese Society of Urology 1979;70:867-873 "Urethral pressure response to hypogastric and pudendal nerve stimulation" Summary of the Invention [Problem to be solved by the invention]

[0007] However, while it was known that the urethral muscles contract when the pudendal nerve or hypogastric nerve is electrically stimulated, causing changes in the pressure inside the urethra, the nerve plexus 14 around the rectum is composed of multiple nerves, not just a single nerve, and therefore was not thought to change the pressure inside the urethra, and there was no way to monitor the nerve plexus 14 around the rectum using changes in the pressure inside the urethra.

[0008] Therefore, the object of the present invention is to provide an examination method and an examination device for examining nerves adjacent to the rectal fascia proper, which can distinguish between nerves and non-nerve tissues around the rectum and examine them. [Means for solving the problem]

[0009] The method for operating a neurological examination device of the present invention has the following configuration: (1) Around the rectal fascia proper In biological tissue be contacted A method for operating a nerve examination device, the method comprising: an electrical stimulation unit; an examination means for detecting a change in the shape of a balloon inserted into a urethra; and a control device, the method comprising: When the electrical stimulation applying unit outputs a low-frequency current, When the inspection means detects a contraction response of the internal urethral muscle, the control device the biological tissue is the nerve, and if the inspection means does not detect a contraction response of the internal urethral muscle, the control device the biological tissueis determined to be tissue other than nerve tissue.

[0010] (2) In the method for operating the neurological examination device described in (1), The control device is configured to If it is determined that the problem has occurred, warning information is output to the operator.

[0011] In addition, the present invention Operated by the method for operating a neurological examination device The neurological examination device has the following configuration. (3) A nerve examination device comprising an electrical stimulation applying unit that applies electrical stimulation to biological tissue, an examination means that detects changes in the shape of a balloon inserted into the urethra, and a control device, Please state in 1) or (2) The device is operated by a method for operating a neurological examination device, and is provided with an indwelling bladder catheter for draining urine, and the indwelling bladder catheter is provided with the balloon at a portion to be inserted into the urethra. It is characterized by: (4) In the nerve testing device described in (3), the testing means is characterized in that it has at least one of (a) a piezoelectric sensor or a strain sensor attached to the surface of the balloon, (b) a flow meter that measures the amount of air flowing out of the balloon, and (c) a pressure meter that measures the pressure inside the balloon.

[0012] (5) In the nerve examination device described in (3), the electric scalpel is provided with an electrical stimulation unit for applying the low-frequency electrical stimulation to the nerve or tissue other than the nerve, and a switch for operating the electrical stimulation unit. (6) A nerve examination device comprising an electrical stimulation applying unit that applies electrical stimulation to biological tissue, an examination means that detects changes in the shape of a balloon inserted into the urethra, and a control device, Please write in 2) It must be operated by the same method as the neurological examination device. , An electric scalpel, a display means or sound output means for conveying the warning information; and, , The display means or the sound output means It is characterized by being attached to an electric scalpel. (7) The nerve examination device described in (6) is characterized in that a switch for applying the low-frequency electrical stimulation is provided on the electric scalpel.

[0013] The method for examining the nerve adjacent to the rectal fascia proper having the above-described configuration has the following functions and effects. (1) The method is characterized by comprising: Step 1 of applying low-frequency electrical stimulation to nerves or tissues other than nerves that are adjacent to the fascia proper recti that surrounds the rectum; Step 2 of detecting a contraction response of the internal urethral muscle using an inspection means that detects a change in the shape of a balloon inserted into the urethra; and Step 3 of determining that the target to which the low-frequency electrical stimulation was applied is a nerve if a contraction response of the internal urethral muscle is detected when the low-frequency electrical stimulation is applied to the nerve or tissue other than the nerve; and determining that the target to which the low-frequency electrical stimulation was applied is a tissue other than the nerve if a contraction response of the internal urethral muscle is not detected during rectal cancer surgery.Therefore, in rectal cancer surgery, before the outer periphery of the fascia proper recti and the nerves and tissues other than the nerves are dissected using an electric scalpel, a low-frequency current is passed through the target to be cut with the electric scalpel to apply electrical stimulation, and when a contraction response of the internal urethral muscle is detected, the surgeon can determine that the target is a nerve, thereby reducing the risk of accidentally damaging the nerve. Here, the nerve plexus 14 around the rectum is far from the urethra, so the amount of change in intraurethral pressure is small, but by directly detecting the contraction response of the internal urethral muscle, the nerves can be identified accurately and precisely.

[0014] When low-frequency electrical stimulation (electrical stimulation with a frequency of 100 Hz or less) is applied to the nerve, the internal urethral muscle contracts first. As the internal urethral muscle contracts, the balloon, which is inflated against the internal urethral muscle, contracts and deforms. As the balloon contracts, the air pressure inside the balloon increases, causing the air to flow outside the body. The increase in intraurethral pressure is measured by a pressure gauge installed outside the body. In Non-Patent Document 3, low-frequency electrical stimulation is applied to the hypogastric nerve or pudendal nerve close to the urethra, which causes a relatively large change in the internal pressure of the balloon, but the nerves near the rectal fascia proper are a little farther from the urethra, so the response to the low-frequency electrical stimulation may be weaker. Therefore, in the present invention, the outer periphery of the inflated balloon is brought into contact with the front inner periphery of the internal urethral muscle, and when the internal urethral muscle contracts, the minute displacement of the outer periphery of the balloon is directly measured, thereby making it possible to reliably and accurately detect the contractile response of the internal urethral muscle.

[0015] That is, a sensor that measures minute displacements is attached to the outer periphery of a balloon that is inserted into the urethra. The control device inflates the balloon, and stores the sensor output when the balloon is in tight contact with the internal urethral muscle all around as an initial value. Then, by applying low-frequency electrical stimulation to the tissue around the rectum, the change in output of the sensor (for example, a strain sensor that can measure minute displacements) can be measured directly, without using intraurethral pressure, to determine whether the internal urethral muscle has contracted. This makes it possible to accurately examine whether a nerve is present, even if there is a distance between the rectum and the urethra.

[0016] (2) In the method for examining the nerve adjacent to the rectal fascia proper as described in (1), there is provided a step 4 of outputting warning information to an operator (e.g., a surgeon performing surgery) when it is determined that the target to which the low-frequency electrical stimulation is applied is the nerve. The contraction response of the internal urethral muscle is detected by the displacement of the balloon surface, and the test results can be communicated to the surgeon in real time as warning information, allowing the surgeon to make quick decisions even during surgery, which is expected to reduce the complication rate without extending the surgery time.

[0017] Furthermore, the nerve examination device used in the nerve examination method for examining nerves adjacent to the rectal fascia proper according to the present invention having the above-described configuration has the following functions and effects. (3) In the nerve examination device used in the method for examining nerves adjacent to the rectal fascia proper described in (1) or (2), the examination means is characterized in that it is integrally attached to the indwelling bladder catheter for draining urine, so that since surgery for rectal cancer takes a long time, the patient is fitted with an indwelling bladder catheter for draining urine. At this time, by attaching the examination means to the indwelling bladder catheter, the patient can undergo the examination without any additional physical burden.

[0018] (4) In the nerve testing device described in (3), the testing means is characterized by having at least one of (a) a piezoelectric sensor or a strain sensor attached to the surface of the balloon, (b) a flow meter that measures the amount of air flowing out of the balloon, and (c) a pressure meter that measures the pressure inside the balloon.When the balloon is inflated and brought into close contact with the inner circumference of the internal urethral muscle, the pressure value measured by the piezoelectric sensor or the strain value measured by the strain sensor (strain gauge) is stored in the control device as an initial value.When the internal urethral muscle contracts, the contraction response of the internal urethral muscle can be detected reliably and accurately by measuring the minute pressure change or minute displacement on the outer circumference of the balloon that is in close contact with the internal urethral muscle. Furthermore, when the balloon deflates, air flows out of the balloon. By detecting this outflow of air with a highly accurate flow meter, it is possible to reliably and accurately detect the contraction response of the internal urethral muscle. In addition, changes in intraurethral pressure can also be measured using AQUARIUS (registered trademark) LT, sold by Edap Technomed Co., Ltd., which makes it possible to reliably and accurately detect the contraction response of the internal urethral muscle based on changes in air pressure inside the balloon.

[0019] (5) The nerve examination device described in (3) is characterized in that the switch for applying the low-frequency electrical stimulation is provided on the electric scalpel. Therefore, the surgeon can simply contact the tip of the electric scalpel with the target tissue during surgery and operate the examination switch to determine whether the tissue that the electric scalpel is contacting is a nerve or a non-nerve tissue, thereby allowing the surgery to be performed quickly and safely.

[0020] (6) In the nerve examination device used in the rectal fascia proximal nerve examination method described in (2), a display means or sound output means for conveying the warning information is attached to the electric scalpel. Therefore, although all of the surgeon's nerves are concentrated around the electric scalpel during surgery, the display means or sound output allows the surgeon to confirm whether the tissue in contact with the electric scalpel is a nerve or a tissue other than a nerve, thereby enabling the surgery to be performed quickly and safely.

[0021] (7) In the nerve examination device described in (6), a switch for applying the low-frequency electrical stimulation is provided on the electric scalpel, and since both the switch and the display means or sound output means are provided on the electric scalpel, the operator's confirmation work can be made easier. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a cross-sectional view of the rectum and surrounding tissues. [Figure 2] This is a diagram showing a tube with a balloon near the tip inserted and attached to the urethra for excreting urine from the bladder. [Figure 3] FIG. 3 is a diagram showing the experimental results of FIG. 2. [Figure 4] 1 is an indwelling bladder catheter equipped with the neurological examination device of the present invention. [Figure 5] 5A is an enlarged view of part A in FIG. 4, and FIG. 5B is a view showing the case where the number of strain sensors is increased to three rows, totaling 12 locations. [Figure 6] FIG. 2 is a cross-sectional view of the balloon cut at the center. [Figure 7] 1A and 1B are diagrams showing the configuration of an electric scalpel according to the present invention. [Figure 8] FIG. 2 is an enlarged perspective view of a scalpel portion at the tip of the electric scalpel. [Figure 9] FIG. 2 is a control configuration diagram of the present nerve examination device. DETAILED DESCRIPTION OF THE INVENTION

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A detailed description will be given of an embodiment of a method for examining nerves adjacent to the rectal fascia proper and a nerve examination device according to the present invention with reference to the drawings. FIG. 4 shows an indwelling bladder catheter 10 equipped with the neurological examination device of the present invention. The indwelling bladder catheter 10 includes a urination funnel 16 and a catheter tube 14 connected to the urination funnel 16. A balloon 11 is provided near the tip of the catheter tube 14, which is inflated with air to fit closely to the inner surface of the internal urethral muscle 51 and prevent urine leakage. While the balloon 11 shown in FIG. 4 is inflated with air, the balloon 11 is deflated when inserted into the urethra, and is inflated by injecting air after insertion. Note that FIG. 4 shows the balloon 11 in a simplified form, and details will be described later with reference to FIG. 5.

[0024] A urine collection tube 18 is provided at the tip of the catheter tube 14, and an inlet hole 13 is opened on the side of the urine collection tube 18 to allow urine to flow into the urine collection tube 18. The urine collection tube 18 passes through the balloon 11 and communicates with the catheter tube 14. As a result, urine taken in through the inlet hole 13 passes through the catheter tube 14 and is discharged into a urine drainage bag (not shown) via the urination funnel 16. A signal line 15 is provided next to the catheter tube 14, and the tip of the signal line 15 is connected to a strain sensor (strain gauge) described below. The other end of the signal line 15 is connected to the control device 12.

[0025] Next, an enlarged view of part A in Fig. 4 is shown in Fig. 5(a), and the balloon 11 will be described in detail. Fig. 4(a) shows the state in which the balloon 11 is inserted into the urethra 50, air is injected into it to expand it, and the outer surface of the balloon 11 is in close contact with the internal urethral muscle 51 that forms the inner surface of the urethra 50. Fig. 6 shows a cross-sectional view of the balloon 11 cut at the center. Four strain sensors 21A, 21B, 21C, and 21D are attached at 90-degree intervals in the circumferential direction on the outer periphery of balloon 11. Strain sensors 21A, 21B, 21C, and 21D are arranged in close contact with intrinsic urethral muscle 51. That is, air is injected into balloon 11 to expand it until balloon 11 and strain sensors 21A, 21B, 21C, and 21D expand intrinsic urethral muscle 51 slightly outward.

[0026] The strain sensors 21A, 21B, 21C, and 21D are positioned so as to be able to detect with high accuracy when the internal urethral muscle 51 undergoes a contraction reaction, i.e., when strain occurs on the surface of the balloon 11 corresponding to the internal urethral muscle 51 in the circumferential direction, which is the direction indicated by the arrow in Figure 6. The reason for providing strain sensors 21A, 21B, 21C, and 21D at four locations is to ensure reliable detection even when a partial contraction response occurs, rather than when the entire internal urethral muscle 51 contracts. Note that it is not necessary to provide four strain sensors; one to three highly accurate strain sensors may be provided.

[0027] Figure 5(b) shows a case where the number of strain sensors is increased to three rows, for a total of 12 locations. Because the internal urethral muscle 51 is located in a specific location of the urethra, with one row of four locations as in Figure 5(a), depending on the patient, the strain sensor 21 may not be able to make proper contact with the internal urethral muscle 51. To avoid this, Figure 5(b) provides three rows of strain sensors 21A, 21B, 21C, 21D, 22A, 22B, 22C, 22D, 23A, 23B, 23C, and 23D. Thus, providing strain sensors at 12 locations has the advantage of being able to reliably detect even partial contraction responses of the internal urethral muscle 51.

[0028] Next, the electric scalpel 30 will be described with reference to Figure 7. The electric scalpel 30 is a medical device that incises and coagulates tissue by passing a high-frequency current of 300 to 400 kHz from a scalpel section 35 at the tip into a human body through a thin metal scalpel tip (arc discharge). In addition to a scalpel switch 31 for the electric scalpel, an examination switch 32 for nerve examination is provided in parallel. The scalpel switch 31 is pressed to perform surgery such as cutting the target tissue, and the examination switch 32 is a switch that passes a current and applies a low-frequency electrical stimulus to the target tissue.

[0029] Figure 8 shows an enlarged perspective view of scalpel part 35 at the tip of electric scalpel 30 (an enlarged perspective view of part B in Figure 7). A surgical electrode 36 for passing a high-frequency current is provided at the center of scalpel part 35. An insulating resin part 37 is disposed on the outside of surgical electrode 36. A first electrode 38 and a second electrode 39 serving as an electrical stimulation applying part are provided on insulating resin part 37 at a predetermined interval. By pressing the test switch 32, a low frequency current flows from the first electrode 38 through the target tissue to the second electrode 39. In this embodiment, a current of 2 Hz to 50 Hz is used as the low frequency current. The electric scalpel 30 shown in FIG. 7 is provided on its upper portion with a green LED 33 and a red LED 34 for displaying the test results.

[0030] In this embodiment, surgical electrode 36 and first electrode 38 and second electrode 39, which are test electrodes, are fixed on the same plane, but insulating resin part 37, which includes first electrode and second electrode, may be configured to be able to move forward and backward along the central axis of surgical electrode 36 relative to surgical electrode 36. By advancing insulating resin part 37 during the test and retracting it during surgery, it is possible to improve the ease of use of surgical electrode 36 for the surgeon (an example of an operator).

[0031] Figure 9 shows a control configuration diagram of this nerve testing device. Indwelling bladder catheter 10 is connected to control device 12, and therefore a first row of strain sensors 21A, 21B, 21C, and 21D are also connected. When indwelling bladder catheter 10 is equipped with balloon 11 shown in Figure 5(b), control device 12 is also connected to first row of strain sensors 21A, 21B, 21C, and 21D, second row of strain sensors 22A, 22B, 22C, and 22D, and third row of strain sensors 23A, 23B, 23C, and 23D. An electric scalpel 30 is connected to the control device 12, along with a surgical electrode 36, a first electrode 38, a second electrode 39, and a green LED 33 and a red LED 34 serving as display means. A scalpel switch 31 and an inspection switch 32 are also connected.

[0032] Next, the operation of the nerve examination apparatus having the above configuration will be described. When performing dissection at a position midway between the DVF 13 and the hypogastric preneurial fascia 5 during surgery for rectal cancer, before using the electric scalpel 30 to dissect the outer periphery of the rectal fascia proper and the nerve and non-nerve tissues, the surgeon brings the first electrode 38 and the second electrode 39 at the tip of the electric scalpel 30 into close contact with the target tissue to be cut with the electric scalpel 30 and presses the test switch 32. This causes a low-frequency current to flow through the target tissue, providing electrical stimulation. When the target tissue is a nerve, contraction of the internal urethral muscle 51 occurs first. Then, as the internal urethral muscle 51 contracts, the balloon 11, which is inflated in contact with the internal urethral muscle 51, contracts and deforms. Then, as the balloon 11 contracts, the strain sensor 21 attached to the outer periphery of the balloon 11 detects the contraction response of the internal urethral muscle 51 and outputs the result to the control device 12.

[0033] When the strain sensor 21 detects a contraction response of the internal urethral muscle 51, the control device 12 determines that the target tissue currently in contact with the first electrode 38 and the second electrode 39 of the electric scalpel 30 is a nerve, and lights up the red LED 34 to convey warning information to the surgeon. Furthermore, when the strain sensor 21 does not detect a contraction response of the internal urethral muscle 51, the control device 12 determines that the target tissue currently in contact with the first electrode 38 and the second electrode 39 of the electric scalpel 30 is tissue other than nerve tissue, and lights up the green LED 33 to communicate safety confirmation information to the surgeon. When performing dissection at an intermediate position between the DVF 3 and the hypogastric anterior fascia 5, the surgeon can determine a possible dissection line by inspecting multiple locations of the tissue surrounding the area to be dissected. That is, by inspecting the tissue (nerve) illuminated by the red LED 34 and determining the dissection line along the tissue other than the nerve illuminated by the green LED 33, the risk of damaging the nerve can be avoided.

[0034] In this embodiment, a strain sensor 21 is used, but other inspection means such as (a) a piezoelectric sensor attached to the surface of the balloon, (b) a flow meter that measures the amount of air flowing out of the balloon, or (c) a pressure gauge that measures the pressure inside the balloon can also be used, and these inspection means can be used in combination as necessary. When a piezoelectric sensor is used, the pressure value measured by the piezoelectric sensor is stored as an initial value in the control device when the balloon is inflated and brought into close contact with the inner circumference of the internal urethral muscle 51. When the internal urethral muscle 51 contracts, the minute pressure change or minute displacement of the outer circumference of the balloon that is in close contact with the internal urethral muscle 51 is measured, thereby making it possible to reliably and accurately detect the contraction response of the internal urethral muscle 51. Furthermore, when a flow meter is used, air flows out of the balloon when it contracts. By detecting this outflow of air with a highly accurate flow meter, it is possible to reliably and accurately detect the contraction response of the internal urethral muscle 51. In addition, changes in intraurethral pressure can be measured using AQUARIUS (registered trademark) LT, sold by Edap Technomed Co., Ltd., as a pressure gauge.By using this, the contraction response of the internal urethral muscle 51 can be detected reliably and accurately based on changes in the air pressure inside the balloon.

[0035] As described above in detail, the nerve examination method and nerve examination device adjacent to the rectal fascia proper according to this embodiment have the following effects. (1) The method is characterized by comprising: Step 1 of applying low-frequency electrical stimulation to nerves or tissues other than nerves that are adjacent to the fascia proper recti 2 that surrounds the rectum 1; Step 2 of detecting a contraction response of the internal urethral muscle 51 using an inspection means (e.g., strain sensor 21) that detects a change in the shape of the balloon 11 inserted into the urethra 50; and Step 3 of determining that the target to which the low-frequency electrical stimulation was applied is a nerve if a contraction response of the internal urethral muscle 51 is detected when the low-frequency electrical stimulation is applied to the nerve or tissues other than nerves; and Step 3 of determining that the target to which the low-frequency electrical stimulation was applied is a tissue other than nerves if a contraction response of the internal urethral muscle 51 is not detected when the low-frequency electrical stimulation is applied to the nerve or tissues other than nerves. Therefore, in a rectal cancer surgery, before the outer periphery of the fascia proper recti 2 and the nerves and tissues other than nerves are dissected using the electric scalpel 30, the surgeon applies electrical stimulation by passing a low-frequency current through the target to be cut with the electric scalpel 30, and when a contraction response of the internal urethral muscle 51 is detected, the surgeon can determine that the target is a nerve, thereby reducing the risk of accidentally damaging the nerve. The nerve plexus 4 around the rectum is far from the urethra 50, so the amount of change in intraurethral pressure is small, but by directly detecting the contraction response of the internal urethral muscle 51, the nerves can be identified accurately and precisely.

[0036] When a low-frequency electrical stimulus (electrical stimulus with a low frequency of 100 Hz or less) is applied to the nerve, contraction of the internal urethral muscle 51 occurs first. Then, as the internal urethral muscle 51 contracts, the balloon 11, which is inflated and in contact with the internal urethral muscle 51, contracts and deforms. Then, as the balloon 11 contracts, the air pressure inside the balloon 11 increases, and the air flows out of the body, which is measured by a pressure gauge installed outside the body. In Patent Document 3, low-frequency electrical stimulation is applied to the hypogastric nerve or pudendal nerve close to the urethra, which causes a relatively large change in the internal pressure of balloon 11, but the nerves near rectal fascia proper 2 are slightly distant from urethra 50, so there is a possibility that the response to the low-frequency electrical stimulation may be weak. For this reason, in this embodiment, the outer periphery of inflated balloon 11 is brought into close contact with the front inner periphery of internal urethral muscle 51, and when internal urethral muscle 51 contracts, the minute displacement of the outer periphery of balloon 11 is measured, thereby making it possible to reliably and accurately detect the contraction response of internal urethral muscle 51.

[0037] That is, a strain sensor 21 that measures minute displacements is attached to the outer periphery of a balloon 11 that is inserted and attached to the urethra 50. The control device 12 stores as an initial value the output of the strain sensor 21 when the balloon 11 is inflated and the entire circumference is in tight contact with the internal urethral muscle 51. Then, based on the change in output of the strain sensor 21, which can measure minute displacements when low-frequency electrical stimulation is applied to the tissue surrounding the rectum 1, it is possible to directly measure whether the internal urethral muscle 51 has contracted, without using intraurethral pressure as an intermediary. Therefore, even if there is a distance between the rectum 1 and the urethra 50, it is possible to accurately examine whether a nerve is present.

[0038] (2) The method for examining nerves adjacent to the rectal fascia proper described in (1) is characterized by having a step 4 of outputting warning information to the surgeon if it is determined that the target to which low-frequency electrical stimulation is applied is a nerve.Since the contraction response of the internal urethral muscle 51 is detected by the displacement of the surface of the balloon 11, the examination results can be transmitted to the surgeon as warning information in real time, allowing the surgeon to make a quick decision even during surgery, and it is expected that the complication rate will be reduced without extending the surgery time.

[0039] Furthermore, the nerve examination device used in the nerve examination method for examining nerves adjacent to the rectal fascia proper according to the present invention having the above-described configuration has the following effects. (3) In the nerve examination device used in the rectal fascia proximal nerve examination method described in (1) or (2), the strain sensor 21, which is the examination means, is integrally attached to the indwelling bladder catheter 10 for draining urine, and since rectal cancer surgery takes a long time, the patient is fitted with the indwelling bladder catheter 10 for draining urine. At this time, by attaching the examination means (strain sensor 21) to the indwelling bladder catheter 10, the patient can undergo the examination without any additional physical burden.

[0040] (5) The nerve examination device described in (3) is characterized in that the electric scalpel 30 is provided with an electrical stimulation applying unit (e.g., the first electrode 38 and the second electrode 39) for applying low-frequency electrical stimulation to nerve or non-nerve tissue, and a switch (examination switch 32) for operating the electrical stimulation applying unit (the first electrode 38 and the second electrode 39).Therefore, the surgeon can simply apply the tip of the electric scalpel 30 to the target tissue during surgery and operate the examination switch 32 to determine whether the tissue in contact with the electric scalpel 30 is a nerve or a non-nerve tissue, thereby allowing the surgery to be performed quickly and safely.

[0041] (6) In the nerve examination device used in the rectal fascia proximal nerve examination method described in (2), a red LED 34, which is a display means for conveying warning information, is attached to the electric scalpel 30. Therefore, although all of the surgeon's nerves are concentrated around the electric scalpel 30 during surgery, the red LED 34 makes it possible to confirm whether the tissue that the electric scalpel 30 is in contact with is a nerve or a tissue other than a nerve, so that the surgery can be performed quickly and safely. In this embodiment, the red LED 34 is used to convey the warning information to the surgeon, but the control device 12 or the electric scalpel 30 may be provided with a sound output means to convey the warning information by generating an alarm sound.

[0042] (7) The nerve examination device described in (6) is characterized in that the electric scalpel 30 is provided with an examination switch 32 for applying low-frequency electrical stimulation. Since the examination switch 32 and the red LED 34, which is a display means, are both provided on the electric scalpel, the operator's confirmation work can be made easier.

[0043] The above describes the method for examining nerves adjacent to the rectal fascia proper and the nerve examination device according to the present invention, but the present invention is not limited to this, and various modifications are possible within the scope of the spirit thereof. For example, in this embodiment, the surgeon memorizes the details of each location checked by the electric scalpel 30 and determines the peeling line from his / her own memory, but the system may also be such that the object is memorized as an image using a camera, and then the surgeon inspects multiple locations of nerve and non-nerve tissue using the first electrode 38 and the second electrode 39, and the inspection positions and inspection results are displayed on the previously memorized image, and the peeling line is indicated by an AI computer based on these inspection results. [Explanation of symbols]

[0044] 1 rectum 2 Fascia propria rectus 3 Denonvilliers Fascia (DVF) 4. Plexus 10 Indwelling bladder catheter 11 Balloon 12 Control device 21 Strain sensor 30 Electric scalpel 32 Inspection switch 33 Green LED 34 red LED 35 Female part 36 Surgical electrodes 37 Insulating resin part 38 1st electrode 39 Second electrode 50 Urethra 51 Internal urethral muscle

Claims

1. A method for operating a nerve examination device, comprising: an electrical stimulation applying unit that contacts biological tissue around the rectal fascia proper; an examination means that detects a change in the shape of a balloon inserted into the urethra; and a control device, comprising: When the electrical stimulation applying unit outputs a low-frequency current, When the inspection means detects a contraction response of the internal urethral muscle, the control device determines that the biological tissue is the nerve, When the inspection means does not detect a contraction response of the internal urethral muscle, the control device determines that the biological tissue is a tissue other than the nerve. A method for operating a neurological examination device, comprising:

2. 2. A method for operating a neurological examination apparatus according to claim 1, comprising: When the control device determines that the biological tissue is a nerve, it outputs warning information to an operator. A method for operating a neurological examination device, comprising:

3. A nerve examination device for operating a nerve examination device, comprising: an electrical stimulation applying unit that applies electrical stimulation to biological tissue; an examination means that detects a change in the shape of a balloon inserted into the urethra; and a control device, When the electrical stimulation applying unit applies low-frequency electrical stimulation to nerves or tissues other than nerves that are adjacent to the rectal fascia that surrounds the rectum, When the inspection means detects a contraction response of the internal urethral muscle, the control device determines that the target to which the low-frequency electrical stimulation is applied is the nerve, When the inspection means does not detect a contraction response of the internal urethral muscle, the control device determines that the target to which the low-frequency electrical stimulation is applied is tissue other than the nerve. A neurological examination device characterized by:

4. The neurological examination device according to claim 3, outputting warning information to an operator when it is determined that the target to which the low-frequency electrical stimulation has been applied is a nerve; A neurological examination device characterized by:

5. A neurological examination device according to claim 3 or claim 4. Equipped with an indwelling bladder catheter for draining urine; the indwelling bladder catheter has the balloon at a portion inserted into the urethra; A neurological examination device characterized by:

6. 6. The neurological examination apparatus according to claim 5, The inspection means (a) a piezoelectric sensor and a strain sensor attached to the surface of the balloon; (b) a flow meter that measures the amount of air flowing out of the balloon; (c) a pressure gauge for measuring the pressure inside the balloon; (a), (b), or (c); A neurological examination device characterized by:

7. 6. The neurological examination apparatus according to claim 5, an electrical stimulation applying unit for applying the low-frequency electrical stimulation to the nerve or tissue other than the nerve; a switch for operating the electrical stimulation applying unit; is provided on the electric scalpel, A neurological examination device characterized by:

8. The neurological examination device according to claim 4, The device is provided with an electric scalpel and a display means or a sound output means for conveying the warning information. the display means or the sound output means is attached to the electric scalpel; A neurological examination device characterized by:

9. 9. The inspection device according to claim 8, a switch for applying the low-frequency electrical stimulation is provided on the electric scalpel; A neurological examination device characterized by:

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