CN117338385A

CN117338385A - Lumbar puncture system and use method thereof

Info

Publication number: CN117338385A
Application number: CN202311239814.6A
Authority: CN
Inventors: 杨亚杰; 郭鑫; 廖静文; 程杰; 王国胜; 余刘洋; 邵玺; 白丹丹; 张春柯; 崔景强; 张菁
Original assignee: Henan Tuoren Medical Device Co ltd
Current assignee: Henan Tuoren Medical Device Co ltd
Priority date: 2023-09-25
Filing date: 2023-09-25
Publication date: 2024-01-05

Abstract

The invention belongs to the technical field of active medical instruments, relates to an anesthetic medical instrument product, and particularly relates to a lumbar puncture system and a using method thereof. The lumbar puncture system has the function of monitoring the puncture position in real time, can realize the visualization of the puncture process, reduces the dependence of the operation on the experience of a clinician, and reduces the puncture failure rate caused by subjective judgment. The puncture device mainly comprises a puncture implementation module and a puncture position real-time monitoring module; the puncture implementation module mainly comprises a puncture needle main body comprising an excitation circuit and a measurement circuit, and the real-time monitoring module mainly comprises a signal excitation part and a signal measurement part which are communicated with each other through the puncture needle main body. The use method can calculate the tissue electrical impedance value according to the voltage near the needle point of the puncture needle main body and the current of the excitation device measured by the signal processor, and reversely deduce the type of the tissue at the position, thereby achieving the purpose of judging whether the puncture position is correct, being safer to use and free from radiation injury.

Description

Lumbar puncture system and use method thereof

Technical Field

The invention belongs to the technical field of active medical instruments, relates to an anesthetic medical instrument product, and particularly relates to a lumbar puncture system and a using method thereof.

Background

Puncturing human tissue is a clinically common examination and treatment means, and various percutaneous puncture treatment techniques are rapidly increasing with the development of minimally invasive surgery. Lumbar puncture is one of the common clinical examination methods, can be used for diagnosing various inflammatory diseases, vascular diseases, vertebrography, lumbar anesthesia and the like of the central nervous system, and has important value in the aspects of diagnosing and treating the diseases of the nervous system and the like.

Among them, epidural anesthesia is one of the most common uses of lumbar puncture, and is mainly an anesthesia mode in which a certain amount of anesthetic is injected into the epidural space by means of a lumbar puncture needle, and the anesthetic acts on nerve fibers in the epidural space, thereby producing an anesthetic effect. The success of anesthesia is directly related to whether the anesthesia needle can accurately reach the epidural space. When the puncture is too shallow, the anesthetic needle does not enter the epidural space, so that the anesthetic effect cannot be achieved, and when the puncture is too deep, the anesthetic needle breaks through the dura mater to penetrate through the arachnoid film, so that the anesthetic is scattered in cerebrospinal fluid and the cerebrospinal fluid is leaked, and serious complications such as headache, cerebral hernia and the like after the puncture operation are caused.

The lumbar puncture needle adopted in clinic at present is generally composed of a lumbar puncture needle with a needle handle and a needle sleeve, wherein the needle handle is communicated with the inner cavity of the needle sleeve, and a needle core with the needle handle can be placed in the inner cavity of the lumbar puncture needle. However, the traditional lumbar puncture needle structure is too simplified, and is often performed under a 'blind view' condition, and the puncture process is guided by the experience of a doctor. In the actual puncturing process, due to the difference of diseases of patients and individual differences of normal human body structures, the experience of clinicians is different, and the problem of inaccurate puncturing depth is inevitably generated in various clinical punctures, so that puncture failure can be caused, and the patients are easily damaged.

Therefore, in order to solve the above problems and improve the success rate of the operation, it is highly desirable to develop an anesthetic needle having a function of monitoring the puncture position in real time, so as to provide reference information for a doctor in clinical operation, improve operation accuracy, reduce excessive dependence of the operation on experience of the clinician, and improve accuracy and safety of the puncture operation.

Disclosure of Invention

Based on the above, the invention aims to provide a lumbar puncture system with a function of monitoring puncture positions in real time.

In order to achieve the above purpose, the present invention adopts the following technical scheme:

the invention provides a lumbar puncture system which has the function of monitoring puncture positions in real time and mainly comprises a puncture implementation module and a puncture position real-time monitoring module 17; the puncture implementing module mainly comprises a puncture needle main body comprising an excitation circuit and a measurement circuit, wherein the puncture needle main body mainly comprises an outer needle mechanism and an inner needle mechanism; the real-time monitoring module 17 mainly comprises a signal excitation part 18 and a signal measurement part 19 which are communicated with each other through the puncture needle body;

wherein the signal excitation part 18 applies excitation signals to the tested tissue and mainly comprises an excitation module 20; the signal measuring part 19 is used for signal monitoring and mainly comprises a signal processing module;

the outer needle mechanism mainly comprises an outer needle base 2 and an outer needle tube 1 which sequentially comprises an inner insulating layer 103, a metal needle tube 101, a middle insulating layer 102, a metal electrode circuit 3 and an outer insulating layer 104 from inside to outside; the inner needle mechanism mainly comprises an inner needle core 8 and an inner needle base 6.

Further, the metal electrode circuit 3 mainly includes a first excitation electrode 301 and a second excitation electrode 302; the first excitation electrode 301 and the second excitation electrode 302 are circular metal sheets with the diameter of 1mm and the thickness of 10nm, and are formed at the position of 1-1.5mm close to the tip of the puncture needle main body by an ion sputtering method.

Further, the metal electrode circuit 3 further includes a first metal wire 303 with a front end welded to the first excitation electrode 301 and a second metal wire 304 with a front end welded to the second excitation electrode 302; the first metal wire 303 and the second metal wire 304 are metal wires having a diameter of 0.5mm formed between the middle insulating layer 102 and the outer insulating layer 104 by an ion sputtering method.

Further, the front end of the outer needle tube 1 is provided with an inclined needle point, and the tail end of the outer needle tube is adhered and fixed in the hollow structure of the outer needle base 2; the middle insulating layer 102 extends to the front 1-1.5cm of the tail end of the metal needle tube 101 to form an insulating part, and the part 1-1.5cm of the tail end of the metal needle tube 101 uncovered by the middle insulating layer 102 is an uninsulated part; the outer needle base 2 comprises a hollow outer needle metal conductive piece 10, the front end of the outer needle metal conductive piece 10 is welded with the tail end of the uninsulated part into a whole, and the outer needle metal conductive piece and the outer needle base shell are integrally installed and formed through hot melt injection molding.

Further, the outer needle base 2 includes an outer needle base inner circuit 7 with a front end welded integrally with the front end of the uninsulated portion, and the outer needle base inner circuit 7 includes an outer needle base inner circuit wire one 701 with a front end welded with the rear end of the metal wire one 303 and a front end welded with the rear end of the metal wire two 304 and having a diameter of 0.5mm, and an outer needle base inner circuit wire two 702 with a front end welded with the rear end of the metal wire two 304.

Further, the inner needle seat inner circuit 4 inside the inner needle seat 6 extends to the circuit interface 5 connected with the rear end real-time monitoring module, and the inner needle seat inner circuit 4 comprises an inner needle seat inner circuit wire one 401, the front end of which is communicated with the outer needle seat inner circuit wire one 701 through a plug-in structure, and an inner needle seat inner circuit wire two 402, the front end of which is communicated with the outer needle seat inner circuit wire two 702 through a plug-in structure.

Further, the inner needle base 6 comprises a hollow insulating isolation block 9 and an inner needle metal conductive piece 11 tightly wrapped outside the tail end of the insulating isolation block 9, and the inner needle metal conductive piece 11 and the inner needle base shell are integrally installed and formed through hot melt injection molding.

Further, the rear end of the inner needle core 8 penetrates through the center of the insulating isolation block 9 and extends to form an inner needle conductive needle electrode 801 connected with the rear end real-time monitoring module. In use, the front end is nested in the outer needle tube 1 and is blocked from the metal needle tube 101 by the inner insulating layer 103.

Further, the exciting circuit is composed of a first exciting electrode 301, a first metal wire 303, a first circuit wire 701 in the outer needle base, a first exciting circuit wire 401, a second exciting electrode 302, a second metal wire 304, a second circuit wire 702 in the outer needle base, and a second exciting circuit wire 402. The measuring circuit is composed of a metal needle tube 101, an outer needle metal conductive piece 10, an inner needle metal conductive piece 11, an inner needle core 8 and an inner needle conductive needle electrode 801, wherein the outer needle metal conductive piece 10 is in contact conduction with the inner needle metal conductive piece 11.

Further, the length of the puncture needle main body is 125mm; when in use, the outer needle mechanism is connected with the inner needle mechanism in a plugging manner; the outer diameter of the outer needle tube 1 is 1.2-1.8mm, the wall thickness is 0.4-0.6mm, and the length is 100mm; the diameter of the inner needle core 8 is 0.6-1.4mm, and the length is 118mm; the inner needle base 2 and the outer needle base 6 both comprise polyethylene plastic materials.

The invention further provides a using method of the lumbar puncture system, which mainly comprises the following steps:

s1, assembling the lumbar puncture system, switching on a power supply, and starting the system;

s2, inserting the puncture needle body into the tissue to be tested, setting current parameters of an excitation module 20, applying current signals to the tissue to be tested through an excitation circuit, and acquiring voltage signals fed back to different tissues through a measurement circuit in the process; the current signal is an alternating current signal, the size of the alternating current signal is 5-10 mu Arms, and the current frequency is 1-10kHz;

s3, processing the voltage signal through a signal processing module, and calculating an impedance value to determine the real-time position of the puncture needle main body; the signal processing module comprises a measuring module 16, an amplifier 21, a filter 22, a demodulator 23, an a/D converter 24, and a signal display and alarm module 25.

Further, the signal processing in S3 mainly includes the following steps:

s31, information acquired by the measuring module 16 is transmitted to the amplifier 21;

s32, the amplifier 21 further expands the signal according to the amplitude of the measured voltage, the expanded signal passes through the filter 22 to eliminate the noise outside the target frequency, and the amplitude and the phase of the signal are calculated;

s33, the amplitude and phase of the signal transmitted by the filter 22 are sinusoidal waveforms proportional to the impedance value of the tissue to be measured, and the demodulator 23 demodulates the analog signal into a digital signal;

s34, the A/D converter 24 digitizes the signal on a chip, and calculates an impedance value from the digitized signal during post-processing.

The invention has the following beneficial effects:

1. the lumbar puncture system provided by the invention has the function of monitoring the puncture position in real time, realizes the visualization of the puncture process, reduces the dependence of the operation on the experience of a clinician, and reduces the puncture failure rate caused by subjective judgment.

2. The puncture needle main body in the lumbar puncture system provided by the invention comprises an excitation circuit and a measurement circuit, wherein the excitation circuit comprises two excitation electrodes, and the measurement circuit comprises two measurement electrodes; the impedance test is carried out by adopting a four-electrode method, and the independent electrode pair for excitation and measurement can avoid the current passing through the measuring electrode and effectively avoid the influence of electrode polarization impedance on tissue impedance.

3. The puncture needle main body in the lumbar puncture system provided by the invention realizes the identification of the puncture tissue by utilizing the bioelectrical impedance technology, and meanwhile, when the puncture needle main body is punctured to a designated position, the rear circuit can be pulled out together with the puncture needle inner core, so that the puncture needle main body has a simpler overall structure, is easy to operate and can be recycled.

4. The lumbar puncture system provided by the invention utilizes the electrical impedance testing technology, which is an electrical signal when being loaded and detected by a human body, has the advantages of lower cost, convenience in use and easiness in manufacturing.

5. The invention provides a using method of a lumbar puncture system, which can accurately measure tissue impedance, can realize continuous puncture process observation, avoids blind puncture of a traditional puncture needle, further improves the success rate of puncture operation, and reduces the generation of complications.

6. The invention provides a using method of a lumbar puncture system, which adopts a safe current signal as an excitation source, is safer to use and has no radiation damage.

Drawings

In order to more clearly illustrate the technical solutions of the present invention, the following description will briefly explain the drawings used in the embodiments or the description of the prior art, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of the overall structure of a lumbar puncture system

FIG. 2 is an exploded view of the main body structure of the puncture needle

FIG. 3 is a schematic side view of the lancet body

FIG. 4 is a schematic side view of an outer needle mechanism and a partially enlarged schematic tip end view

FIG. 5 is an enlarged schematic view of the side section of the outer needle mechanism and the internal structure of the outer needle tube

FIG. 6 is a schematic view of a needle tip structure

FIG. 7 is a schematic side view of an inner needle mechanism

FIG. 8 is a schematic side cross-sectional view of an inner needle mechanism

FIG. 9 is an enlarged schematic view of the cross section of the side and base of the lancet body

FIG. 10 is a sectional view and enlarged schematic view showing the internal structure of the outer needle base

Figure 11 is a simulated view of the lumbar puncture system during use

FIG. 12 is a graph of real-time impedance in an embodiment of the invention

In the figure: 1 is an outer needle tube, 101 is a metal needle tube, 102 is a middle insulating layer, 103 is an inner insulating layer, 104 is an outer insulating layer, 2 is an outer needle base, 3 is a metal electrode circuit, 301 is a first exciting electrode, 302 is a second exciting electrode, 303 is a first metal wire, 304 is a second metal wire, 4 is an inner needle base inner circuit, 401 is an inner needle base inner circuit wire, 402 is an inner needle base inner circuit wire, 5 is a circuit interface, 6 is an inner needle base, 7 is an outer needle base inner circuit, 701 is an outer needle base inner circuit wire, 702 is an outer needle base inner circuit wire, and the device comprises an inner needle core 8, an inner needle conductive needle electrode 801, an insulating isolation block 9, an outer needle metal conductive piece 10, an inner needle metal conductive piece 11, skin 12, a yellow ligament 13, an epidural space 14, an dura mater 15, a measuring module 16, a puncture position real-time monitoring module 17, a signal excitation part 18, a signal measuring part 19, an excitation module 20, an amplifier 21, a filter 22, a demodulator 23, an A/D converter 24, a signal display and alarm module 25, an impedance curve 26, a fat impedance 27 and a muscle impedance 28.

Description of the embodiments

The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments are all implemented on the premise of the technical scheme of the invention, and detailed implementation process is given, but it is to be stated that the protection scope of the invention is not limited to the following embodiments.

As shown in the overall structure schematic diagram of the lumbar puncture system shown in fig. 1, the lumbar puncture system provided by the invention mainly comprises a puncture implementation module taking a puncture needle main body as a core, a puncture position real-time monitoring module 17 and a puncture position real-time monitoring module, wherein the puncture position real-time monitoring module mainly comprises a signal excitation part 18 and a signal measurement part 19 which are communicated through the puncture needle main body. The signal excitation section 18 applies an excitation signal to the tissue under test and mainly includes an excitation module 20. The signal measuring section 19 performs signal detection mainly including a signal processing module. The signal processing module comprises a measuring module 16, an amplifier 21, a filter 22, a demodulator 23, an a/D converter 24 and a signal display and alarm module 25. The puncture system has the function of monitoring the puncture position in real time, can realize the visualization of the puncture process, reduces the dependence of the operation on the experience of a clinician, and reduces the puncture failure rate caused by subjective judgment.

As shown in fig. 2 to 10, the length of the puncture needle main body is generally 125mm, and the puncture needle main body comprises an excitation circuit and a measurement circuit, wherein the excitation circuit and the measurement circuit comprise an outer needle mechanism and an inner needle mechanism which are made of polyethylene plastics, and when the puncture needle main body is in use, the inner needle mechanism needs to be nested in the outer needle mechanism, and the two mechanisms are connected in an inserting mode.

The outer needle mechanism comprises an outer needle tube 1 and an outer needle base 2. The outer diameter of the outer needle tube 1 is 1.2-1.8mm, the wall thickness is 0.4-0.6mm, the length is 100mm, the forefront end of the outer needle tube is provided with an inclined needle point, and the tail end of the outer needle tube is fixedly adhered in the hollow structure of the outer needle base 2. The outer needle tube 1 is sequentially provided with an inner insulating layer 103, a metal needle tube 101, a middle insulating layer 102, a metal electrode circuit 3 and an outer insulating layer 104 from inside to outside.

The metal electrode circuit 3 mainly comprises a first excitation electrode 301 and a second excitation electrode 302, and further comprises a first metal wire 303 with the front end welded with the first excitation electrode 301 and a second metal wire 304 with the front end welded with the second excitation electrode 302; the first excitation electrode 301 and the second excitation electrode 302 are circular metal sheets with a diameter of 1mm and a thickness of 10nm, and are formed at a position of 1-1.5mm close to the tip of the puncture needle main body by an ion sputtering method. The first metal wire 303 and the second metal wire 304 are metal wires having a diameter of 0.5mm formed between the middle insulating layer 102 and the outer insulating layer 104 by an ion sputtering method, and preferably the first metal wire 303 and the second metal wire 304 are platinum wires.

The middle insulating layer 102 extends to a position 1-1.5cm in front of the tail end of the metal needle tube 101 to form an insulating part. The part 1 cm to 1.5cm of the tail end of the metal needle tube 101 which is not covered by the middle insulating layer 102 is an uninsulated part. The front end of the outer needle metal conductive piece 10 inside the outer needle base 2 is welded with the tail end of the uninsulated part of the tail end of the metal needle tube 101 into a whole, and is integrally installed and formed with the outer needle base shell through hot melt injection molding. The outer needle base 2 comprises an outer needle base inner circuit 7 with the front end welded with the front end of the uninsulated part, and the outer needle base inner circuit 7 comprises an outer needle base inner circuit wire one 701 with the front end welded with the rear end of the metal wire one 303 and the diameter of 0.5mm and an outer needle base inner circuit wire two 702 with the front end welded with the rear end of the metal wire two 304. Preferably, the first outer needle base inner circuit wire 701 and the second outer needle base inner circuit wire 702 are conductive copper wires with a diameter of 0.5 mm.

The inner needle mechanism comprises an inner needle core 8 and an inner needle base 6. The diameter of the inner needle tube 8 is 0.6-1.4mm, and the length is 118mm.

The inner needle seat inner circuit 4 inside the inner needle seat 6 extends to a circuit interface 5 connected with the rear end real-time monitoring module, and the inner needle seat inner circuit 4 is welded with the outer needle seat inner circuit 7, and specifically comprises an inner needle seat inner circuit wire one 401, the front end of which is communicated with the outer needle seat inner circuit wire one 701 through a plug-in structure, and an inner needle seat inner circuit wire two 402, the front end of which is communicated with the outer needle seat inner circuit wire two 702 through a plug-in structure. The inner needle base 6 also comprises a hollow insulating isolation block 9 and an inner needle metal conductive piece 11 tightly wrapped outside the tail end of the insulating isolation block. The inner needle metal conductive piece 11 and the inner needle base shell are integrally formed through hot melt injection molding.

The rear end of the inner needle core 8 penetrates through the center of the insulating isolation block 9 and extends to form an inner needle conductive needle electrode 801 connected with the rear end real-time monitoring module. In use, the front end is nested in the outer needle cannula 1 and is blocked from the metallic needle cannula 101 by the inner insulating layer 103.

When in use, the inner needle mechanism is nested in the outer needle mechanism, and the circuits inside the inner needle mechanism and the outer needle mechanism jointly form an excitation circuit and a measurement circuit. The excitation circuit is composed of a first excitation electrode 301, a first metal wire 303, a first circuit wire 701 in the outer needle base, a first excitation circuit wire 401, a second excitation electrode 302, a second metal wire 304, a second circuit wire 702 in the outer needle base, and a second excitation circuit wire 402. The measuring circuit is composed of a metal needle tube 101, an outer needle metal conductive member 10, an inner needle metal conductive member 11, an inner needle core 8 and an inner needle conductive needle electrode 801, wherein the outer needle metal conductive member 10 is in contact conduction with the inner needle metal conductive member 11. And then the excitation electrode and the measurement electrode of the puncture needle main body are communicated with the puncture position real-time monitoring module, so that the puncture needle can be started to be used.

The invention further provides a using method of the lumbar puncture system, which is shown in a simulated view of the using process of the lumbar puncture system in fig. 11, and mainly comprises the following steps:

s1, assembling a lumbar puncture system, switching on a power supply, and starting the system;

s2, inserting the puncture needle body into the tissue to be tested, setting current parameters of an excitation module 20, and applying an alternating current signal with the frequency of 1-10kHz to the tissue to be tested through a first excitation electrode 301 and a second excitation electrode 302 in an excitation circuit; the puncture needle body sequentially punctures the human tissue skin 12 and the ligamentum flavum 13 towards the lumbar dura mater external cavity 14 until reaching the dura mater 15, and acquires voltage signals fed back to different tissues through the electrode metal needle tube 101 and the inner needle core 8 in the measuring circuit;

s3, processing the voltage signal through a signal processing module, and calculating an impedance value to determine the real-time position of the puncture needle main body. When the needle tip of the puncture needle reaches the target position epidural space 14, the feedback impedance value reaches a set threshold value, the alarm gives an alarm signal, and the puncture end point is determined according to the feedback impedance value. The signal processing process mainly comprises the following steps:

s33, the amplitude and the phase of the signal transmitted by the filter 22 are sinusoidal waveforms proportional to the impedance value of the tissue to be detected, and the demodulator 23 demodulates the analog signal into a digital signal;

s34, the A/D converter 24 digitizes the signal on a chip, and the impedance value is calculated by the digitized signal in the post-processing process.

The principle of the invention is as follows: the stimulating current flows through the biological tissue to form an electric field, and the impedance values of various tissues are different due to different components, so that the tissue impedance value can be calculated according to the voltage near the needle point of the puncture needle and the current of the excitation equipment, which are measured by the signal processor, and the type of the tissue at the position can be reversely deduced, thereby achieving the aim of judging whether the puncture position is correct.

Fig. 12 illustrates an exemplary change in the impedance of the lancet body as it pierces the fat and muscle tissue, the signal display of the lancet body and the impedance profile displayed in the alarm module 25 being shown as a line impedance profile 26, the impedance profile 26 being greater than or equal to the fat impedance 27, indicating that the needle tip of the lancet body is moving in the fat, and if the impedance profile 26 does not exceed the muscle impedance 28, indicating that the needle tip of the lancet body is in the muscle tissue.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. The lumbar puncture system is characterized by having the function of monitoring puncture positions in real time and mainly comprising a puncture implementation module and a puncture position real-time monitoring module (17); the puncture implementing module mainly comprises a puncture needle main body comprising an excitation circuit and a measurement circuit, wherein the puncture needle main body mainly comprises an outer needle mechanism and an inner needle mechanism; the real-time monitoring module (17) mainly comprises a signal excitation part (18) and a signal measurement part (19) which are communicated with each other through the puncture needle body;

wherein the signal excitation part (18) applies excitation signals to the tested tissue and mainly comprises an excitation module (20); the signal measuring part (19) is used for signal monitoring and mainly comprises a signal processing module;

the outer needle mechanism mainly comprises an outer needle base (2) and an outer needle tube (1) which sequentially comprises an inner insulating layer (103), a metal needle tube (101), a middle insulating layer (102), a metal electrode circuit (3) and an outer insulating layer (104) from inside to outside; the inner needle mechanism mainly comprises an inner needle core (8) and an inner needle base (6).

2. Lumbar puncture system according to claim 1, characterized in that the metal electrode circuit (3) mainly comprises a first excitation electrode (301) and a second excitation electrode (302); the first excitation electrode (301) and the second excitation electrode (302) are circular metal sheets with the diameter of 1mm and the thickness of 10nm, and are formed at the position of 1-1.5mm close to the tip of the puncture needle main body by an ion sputtering method.

3. The lumbar puncture system according to claim 2, wherein the metal electrode circuit (3) further comprises a first metal wire (303) having a front end welded to the first excitation electrode (301) and a second metal wire (304) having a front end welded to the second excitation electrode (302); the first metal wire (303) and the second metal wire (304) are metal wires with the diameter of 0.5mm which are formed between the middle insulating layer (102) and the outer insulating layer (104) through an ion sputtering method.

4. The lumbar puncture system according to claim 1, wherein the front end of the outer needle tube (1) is a bevel needle point, and the tail end is adhered and fixed in the hollow structure of the outer needle base (2); an insulating part is formed at the position 1-1.5cm in front of the tail end of the metal needle tube (101) extending to the middle insulating layer (102), and an uninsulated part is formed at the position 1-1.5cm in front of the tail end of the metal needle tube (101) uncovered by the middle insulating layer (102); the outer needle base (2) comprises a hollow outer needle metal conductive piece (10) inside, the front end of the outer needle metal conductive piece (10) is welded with the tail end of the uninsulated part into a whole, and the outer needle metal conductive piece and the outer needle base shell are integrally installed and formed through hot melt injection molding.

5. The lumbar puncture system according to claim 4, wherein the outer needle base (2) comprises an outer needle base inner circuit (7) with a front end welded integrally with the front end of the uninsulated portion, and the outer needle base inner circuit (7) comprises an outer needle base inner circuit wire one (701) with a front end welded with the rear end of the metal wire one (303) and a front end welded with the rear end of the metal wire two (304) and with a diameter of 0.5mm, and the outer needle base inner circuit wire two (702) is welded with the front end welded with the rear end of the metal wire two (304).

6. The lumbar puncture system according to claim 5, wherein the inner needle seat inner circuit (4) inside the inner needle seat (6) extends to a circuit interface (5) connected with the rear end real-time monitoring module, and the inner needle seat inner circuit (4) comprises an inner needle seat inner circuit wire one (401) of which the front end is communicated with the outer needle seat inner circuit wire one (701) through a plug structure and an inner needle seat inner circuit wire two (402) of which the front end is communicated with the outer needle seat inner circuit wire two (702) through a plug structure.

7. Lumbar puncture system according to claim 1, characterized in that the inner needle base (6) comprises a hollow insulating isolation block (9) and an inner needle metal conductive piece (11) tightly wrapped outside the tail end of the insulating isolation block (9), wherein the inner needle metal conductive piece (11) and the inner needle base shell are integrally formed by hot melt injection molding.

8. The lumbar puncture system according to claim 7, characterized in that the rear end of the inner needle core (8) penetrates through the center of the insulating spacer (9) and extends to form an inner needle conductive needle electrode (801) connected with the rear end real-time monitoring module, and in use, the front end is nested in the outer needle tube (1) and blocked from the metal needle tube (101) by the inner insulating layer (103).

9. The lumbar puncture system of any of claims 1-8, wherein the puncture needle body is 125mm in length; when in use, the outer needle mechanism is connected with the inner needle mechanism in a plugging manner; the outer diameter of the outer needle tube (1) is 1.2-1.8mm, the wall thickness is 0.4-0.6mm, and the length is 100mm; the diameter of the inner needle core (8) is 0.6-1.4mm, and the length is 118mm; the inner needle base (2) and the outer needle base (6) are made of polyethylene plastic materials.

10. A method of using the lumbar puncture system of claim 9, comprising the steps of:

s2, inserting the puncture needle body into the tissue to be tested, setting current parameters of an excitation module (20), applying current signals to the tissue to be tested through an excitation circuit, and acquiring voltage signals fed back to different tissues through a measurement circuit in the process; the current signal is an alternating current signal, the size of the alternating current signal is 5-10 mu Arms, and the current frequency is 1-10kHz;

s3, processing the voltage signal through a signal processing module, and calculating an impedance value to determine the real-time position of the puncture needle main body; the signal processing module comprises a measuring module (16), an amplifier (21), a filter (22), a demodulator (23), an A/D converter (24) and a signal display and alarm module (25).

11. The method of claim 10, wherein the signal processing in S3 mainly comprises the steps of:

s31, conveying information acquired by the measuring module (16) to the amplifier (21);

s32, the amplifier (21) further expands the signal according to the amplitude of the measured voltage, the expanded signal passes through the filter (22) to eliminate the noise outside the target frequency, and the amplitude and the phase of the signal are calculated;

s33, the amplitude and the phase of the signal transmitted by the filter (22) are sinusoidal waveforms proportional to the impedance value of the tissue to be detected, and the demodulator (23) demodulates the analog signal into a digital signal;

s34, the A/D converter (24) digitizes the signal on a chip, and calculates an impedance value through the digitized signal in the post-processing process.

12. The method of any one of claims 10 or 11, wherein the excitation circuit is formed by a first excitation electrode (301), a first metal wire (303), a first circuit wire (701) in the outer needle base, a first excitation circuit wire (401) and a second excitation electrode (302), a second metal wire (304), a second circuit wire (702) in the outer needle base, and a second excitation circuit wire (402).

13. The use according to any one of claims 10 or 11, wherein the measuring circuit is constituted by a metal needle tube (101), an outer needle metal conductive member (10), an inner needle metal conductive member (11), an inner needle core (8) and an inner needle conductive needle electrode (801), wherein the outer needle metal conductive member (10) is in contact with the inner needle metal conductive member (11) for electrical conduction.