Pressure measuring tube for lumbar puncture and puncture tool

Abstract

The invention discloses a pressure measuring tube for lumbar puncture and a puncture tool, and relates to the field of medical appliances, the pressure measuring tube comprises a tube body, one end of the tube body is a liquid inlet for cerebrospinal fluid to enter the tube body, and the other end of the tube body is a communication port for communicating the interior of the tube body with external air; an elastic film used for cutting off communication between the communication opening and the liquid inlet is arranged in the tube body, and the elastic film has elasticity; pressure scales are marked on the tube body from the position where the tube body is connected with the elastic film to the communication port, and the pressure value of the pressure scale closer to the communication port is larger; the puncture tool comprises a puncture sheath and a piezometric tube, and the piezometric tube is connected with the puncture sheath. According to the invention, the pressure intensity of cerebrospinal fluid can be accurately obtained only by keeping the piezometric tube upward without keeping the piezometric tube vertical, the structure is simple, and the production cost is low.

Description

Technical Field

[0001] The present invention relates to the field of medical instruments, and particularly to a manometer tube and a puncture tool for lumbar puncture. Background Art

[0002] Lumbar puncture is one of the commonly used examination methods in neurology clinics, which is of great value for the diagnosis and treatment of nervous system diseases, simple and easy to perform, and the operation is relatively safe. During the process of obtaining cerebrospinal fluid by lumbar puncture, a manometer tube is connected before releasing the fluid to measure the cerebrospinal fluid pressure.

[0003] When measuring the cerebrospinal fluid pressure, the most common method is to connect a manometer tube to a puncture needle or a puncture sheath (collectively referred to as a puncture sheath for convenience), and the manometer tube is assembled in a vertically upward posture; the manometer tube has scales, and the cerebrospinal fluid enters the manometer tube after passing through the puncture sheath. The cerebrospinal fluid in the manometer tube has a certain height, and this height is the pressure of the cerebrospinal fluid. For adults, the normal range of cerebrospinal fluid in the lying position is 0.78 - 1.76 Kpa (i.e., 80 - 180 mmH2O); for children, the normal range of cerebrospinal fluid in the lying position is 0.4 - 1.0 Kpa (i.e., 40 - 100 mmH2O); based on this basic scheme, more scheme researches have been achieved, such as Chinese patents with publication numbers CN111419209B, CN220404036U, etc. For this method, it is necessary to ensure that the manometer tube is in a vertical state, that is, the axis of the manometer tube is perpendicular to the horizontal plane, so as to ensure that the liquid level of the cerebrospinal fluid is perpendicular to the axis of the tube, thereby ensuring accurate reading; however, it is relatively difficult for a person to hold the manometer tube and keep it in a vertical state.

[0004] Therefore, those skilled in the art have thought of installing a pressure sensor in the manometer tube to detect the pressure of the cerebrospinal fluid; such as the "A cerebrospinal fluid pressure measuring device and method for lumbar puncture" disclosed in Chinese patent with publication number CN115956893A. For a disposable puncture tool, the use cost of the pressure sensor is relatively high, and components such as a controller are also required to cooperate with the pressure sensor, which has the defects of complex structure and high cost while being complex.

[0005] Therefore, based on the above description, a new solution is needed in this field to measure the pressure of cerebrospinal fluid. Summary of the Invention

[0006] The purpose of the present invention is to provide a manometer tube and a puncture tool for lumbar puncture, which only need to keep the manometer tube in an upward state, and can accurately obtain the cerebrospinal fluid pressure without keeping it in a vertical state, with a simple structure and low production cost.

[0007] The technical solution adopted by the present invention is as follows: A manometer tube for lumbar puncture, comprising a tube body. One end of the tube body is a liquid inlet for cerebrospinal fluid to enter the interior of the tube body, and the other end of the tube body is a communication port for the interior of the tube body to communicate with the outside air. An elastic film for blocking the communication between the communication port and the liquid inlet is arranged inside the tube body, and the elastic film has elasticity. On the tube body, pressure scales are marked from the position where the tube body is connected to the elastic film to the communication port, and the pressure values of the pressure scales closer to the communication port are larger.

[0008] Further, a pointer for indicating the pressure scale is fixed on the side of the elastic film facing the communication port, and the pointer is slidably connected to the inner wall of the tube body.

[0009] Further, the pointer is in clearance fit with the inner wall of the tube body.

[0010] Further, the elastic film and the tube body are hermetically connected by sealant; or the tube body comprises a first section and a second section connected by flange sealing. A groove is provided on the flange of the first section, and a convex ring matching the groove is provided on the flange of the second section. After the first section and the second section are connected, the convex ring is located in the groove and clamps the outside of the elastic film.

[0011] A puncture tool, comprising a puncture sheath and the manometer tube for lumbar puncture as described above. The liquid inlet is hermetically and fixedly connected to the middle of the puncture sheath, and the liquid inlet communicates with the interior of the puncture sheath. A first valve is provided on the puncture sheath, and the installation position of the first valve is between the position where the puncture sheath is connected to the liquid inlet and the liquid outlet of the puncture sheath.

[0012] Further, a connecting portion for hermetically connecting with the puncture sheath is provided on the tube body at the liquid inlet.

[0013] Further, the connecting portion is the end face of the tube body, and the end face of the tube body is hermetically and fixedly connected to the puncture sheath.

[0014] Further, a branch pipe is provided in the middle of the puncture sheath, and an internal thread is provided on the inner wall of the branch pipe; the connecting portion is an external thread provided on the outer surface of the tube body, and the external thread can be threadedly connected with the internal thread. A sealing member is provided between the tube body and the branch pipe.

[0015] Further, the sealing member is a water-stop tape, and the water-stop tape is wrapped on the external thread.

[0016] Further, the sealing member is a sealing ring. An annular pressing block is fixed on the outer surface of the tube body, and the sealing ring is fixed on the annular pressing block. The sealing ring can be pressed between the annular pressing block and the end face of the branch pipe.

[0017] Further, a second valve is provided on the branch pipe or the tube body.

[0018] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows: 1. For the present invention, only the pressure measuring tube needs to be kept upward, and accurate cerebrospinal fluid pressure can be obtained without keeping it in a vertical state. 2. The present invention has a simple structure, does not use a pressure sensor, has a low production cost, and meets the requirements of disposable use. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be described by way of examples with reference to the accompanying drawings, where: Figure 1 is a schematic structural diagram of the present invention; Figure 2 is Figure 1 an enlarged schematic diagram of part A in Figure 3 is a schematic diagram of the present invention in a balanced state during pressure measurement; Figure 4 is an installation schematic diagram of the elastic film; Figure 5 is a connection schematic diagram of the tube body and the puncture sheath; Markings in the figure: 1 - tube body, 11 - liquid inlet, 12 - communication port, 13 - pressure scale, 14 - external thread, 15 - first section, 16 - second section, 2 - puncture sheath, 21 - branch pipe, 22 - internal thread, 3 - elastic film, 4 - pointer, 5 - first valve, 6 - second valve, 7 - annular pressing block, 8 - sealing ring, 9 - flange, 91 - convex ring; 92 - groove. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] In the description of this specification, it should be noted that if terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this specification is usually placed during use. It is only for the convenience of describing this specification and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to this specification.

[0021] In addition, terms such as "horizontal" and "vertical" in the description of this specification do not mean that the components are required to be absolutely horizontal or hanging vertically, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0022] In the description of this specification, it should also be noted that unless otherwise clearly specified and defined, the terms "set", "installed", "connected", and "linked" should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components.

[0023] Embodiment 1 As Figures 1 - 5 shown, a manometer tube used for lumbar puncture includes a tube body 1. One end of the tube body 1 is a liquid inlet 11, and cerebrospinal fluid can enter the tube body 1 from the liquid inlet 11, pushing the air inside the tube body 1; the other end of the tube body 1 is a communication port 12, and the outside air is communicated with the inside of the tube body 1 through the communication port 12, so that the pressure measurement is the pressure relative to the atmospheric pressure. As known from the background technology, the pressure of cerebrospinal fluid is a relative pressure; an elastic film 3 is arranged inside the tube body 1. The elastic film 3 is located between the liquid inlet 11 and the communication port 12, and the elastic film 3 is hermetically and fixedly connected to the inner wall of the tube body 1, so that the elastic film 3 separates the communication port 12 from the liquid inlet 11; on the tube body 1, pressure scales 13 are marked from the position where the tube body 1 is connected to the elastic film 3 to the communication port 12, and the pressure value of the pressure scale 13 closer to the communication port 12 is larger.

[0024] In this embodiment, the working mode of the manometer tube is as follows: As Figure 3 shown, when the tube body 1 is upward, cerebrospinal fluid flows into the tube body 1 from the liquid inlet 11 after passing through the puncture sheath 2. During this process, the cerebrospinal fluid will continuously push the air inside the tube body 1 until it reaches an equilibrium state and the cerebrospinal fluid no longer enters the tube body 1. At this time, the air pressure p1 inside the tube body 1 is equal to the pressure p0 of the cerebrospinal fluid, that is, p1 = p0; the air inside the tube body 1 is pushed and is in a positive relative pressure state, so it will squeeze the elastic film 3, and the elastic film 3 undergoes an expansion deformation, that is, the elastic film 3 expands towards the position where the communication port 12 is located until it reaches an equilibrium state, that is, p1 = p2 + p3, where: p2 is the atmospheric pressure, and p3 is the pressure generated by the elastic force of the elastic film 3; it can be known that since p2 is a constant, p3 has a linear relationship with p1, that is, p3 has a linear relationship with p0; since the magnitude of p3 is manifested in the deformation amount of the elastic film 3, p0 has a linear relationship with the deformation amount of the elastic film 3; thus, only by measuring the deformation amount of the elastic film 3 can the magnitude of p0 be obtained; in this embodiment, the pressure scale 13 reflects the deformation amount of the elastic film 3, so that p0 can be visually presented.

[0025] It should be noted that the specific value indicated by the pressure scale 13 can be obtained through a limited number of tests.

[0026] In this embodiment, the material of the elastic film 3 is preferably latex, and its high material strength, large elasticity, and uniform thickness fully meet the requirements of this embodiment.

[0027] To sum up, the pressure of the cerebrospinal fluid is reflected in the deformation of the elastic film 3. The elastic film 3 has no fluidity and is restricted by the tube body 1. The pressure is not determined by the liquid level height of the cerebrospinal fluid inside the tube body 1. Therefore, when measuring the pressure, it is not necessary to ensure that the tube body 1 is in a vertical state to accurately obtain the cerebrospinal fluid pressure; moreover, setting the diaphragm will not cause the cerebrospinal fluid to come into contact with the atmosphere during pressure measurement, thereby reducing the risk of cerebrospinal fluid contamination; the structure is simple, no pressure sensor is used, the production cost is low, and it meets the requirements of single-use.

[0028] Embodiment 2 On the basis of Embodiment 1, a further feasible specific implementation method is proposed.

[0029] In a feasible implementation method, in Embodiment 1, the value is read by aligning the position where the elastic film 3 is deformed with the corresponding pressure scale 13. Since the elastic film 3 is in the state of an arc head inside the tube body 1, when reading the value, the line of sight needs to be perpendicular to the axis of the tube body 1 to accurately read the value. Therefore, it is easy to cause inaccurate reading due to the line of sight angle; for this reason, in order to intuitively read the value, a pointer 4 for indicating the pressure scale 13 is fixed on the side of the elastic film 3 facing the communication port 12. The pointer 4 is slidably connected to the inner wall of the tube body 1, and the pointer 4 can move following the expansion and deformation of the elastic film 3.

[0030] Furthermore, the pointer 4 and the inner wall of the tube body 1 are in clearance fit to reduce the friction between the pointer 4 and the tube body 1 and avoid affecting the measurement of the cerebrospinal fluid pressure.

[0031] In a feasible implementation method, regarding the fixed connection between the elastic film 3 and the tube body 1, the following several feasible implementation methods are proposed.

[0032] In the first implementation method, the sealed connection between the elastic film 3 and the tube body 1 can be realized by using a sealant for sealed fixed connection. The sealant is a commonly used material in the art, such as epoxy resin, etc.

[0033] In the second embodiment, the tube body includes a first section 15 and a second section 16 that are hermetically connected by a flange 9. A groove 92 is provided on the flange 9 of the first section 15, and a convex ring 91 that matches the groove 92 is provided on the flange 9 of the second section 16. After the first section 15 and the second section 16 are connected, the convex ring 91 is located within the groove 92 and clamps the outside of the elastic film 3; the hermetic and fixed connection of the flange 9 can be achieved by screwing bolts. The connection method of the flange 9 is well-known to those skilled in the art and will not be described in detail in this specification; on the one hand, the convex ring 91 and the groove 92 cooperate to form a labyrinth seal, ensuring the sealing performance at the connection position between the first section 15 and the second section 16; further squeezing the elastic film 3 not only strengthens the sealing performance but also effectively fixes the elastic film.

[0034] It should be noted that in the first embodiment, due to the presence of the sealant, for the sealant to fix the elastic film 3, the elastic film 3 will surely be cured. However, it is difficult to maintain consistency in the degree and area of curing in the circumferential direction, which easily causes uneven deformation of the elastic film 3, further leading to inaccurate measurement; in addition, when the elastic film 3 is cured, the brittleness and hardness also increase. After the amount of deformation of the elastic film 3 increases to a certain extent, the cured position of the elastic film 3 is prone to breakage, resulting in the inability to complete the measurement; while the fixing method disclosed in the second embodiment does not require sealant compared to the first embodiment, and there is no phenomenon of the sealant curing the elastic film 3, so the measurement can be more accurate. Therefore, the second embodiment is preferably used to fix the elastic film.

[0035] Example 3 Such as Figures 1 - 5 , a puncture tool includes a puncture sheath 2 and a pressure measuring tube for lumbar puncture described in any one of Examples 1-2. The liquid inlet 11 is hermetically and fixedly connected to the middle of the puncture sheath 2, and the liquid inlet 11 is in communication with the inside of the puncture sheath 2. After the puncture sheath 2 completes the puncture, cerebrospinal fluid can enter the puncture sheath 2 from the front end of the puncture sheath 2 and further enter the tube body 1 from the liquid inlet 11; a first valve 5 is provided on the puncture sheath 2, and the installation position of the first valve 5 is between the connection position of the puncture sheath 2 and the liquid inlet 11 and the liquid outlet of the puncture sheath 2, to prevent cerebrospinal fluid from flowing out of the liquid outlet of the puncture sheath 2 during the measurement of pressure, resulting in the failure of pressure measurement.

[0036] Specifically, when measuring the cerebrospinal fluid pressure, the first valve 5 needs to be closed, forcing the cerebrospinal fluid to flow only into the tube body 1; after the pressure measurement is completed, the first valve 5 is opened, and medical staff can collect cerebrospinal fluid at the liquid outlet position of the puncture sheath 2.

[0037] Example 4 On the basis of Example 3, a further feasible specific implementation method is proposed.

[0038] As can be seen from the above, it is necessary to ensure the sealing inside the tube body 1 between the liquid inlet 11 and the elastic film 3. Therefore, a connecting portion for sealing connection with the puncture sheath 2 is provided on the tube body 1 at the liquid inlet 11 to ensure the sealing connection between the tube body 1 and the puncture sheath 2 and avoid leakage at the connection position, which may affect the pressure measurement result.

[0039] In this embodiment, several feasible implementation manners are proposed for the connecting portion.

[0040] In the first implementation manner, the connecting portion is the end face of the tube body 1, and the end face of the tube body 1 is fixedly and sealingly connected to the puncture sheath 2, that is, the tube body 1 and the puncture sheath 2 are an integral body and are not detachable; it can be integrally formed by injection molding or the like during manufacturing, or the above-mentioned sealant can be used to achieve the sealing and fixing connection.

[0041] As Figure 4 shown, in the second implementation manner, a branch pipe 21 is provided in the middle of the puncture sheath 2, and an internal thread 22 is provided on the inner wall of the branch pipe 21; the connecting portion is an external thread 14 provided on the outer surface of the tube body 1, and a seal is provided between the tube body 1 and the branch pipe 21. The tube body 1 is fixedly connected to the puncture sheath 2 by screwing the external thread 14 and the internal thread 22, and the connection position is sealed by the seal.

[0042] It should be noted that for the second implementation manner, the puncture sheath 2 and the branch pipe 21 are detachable and can be assembled on site during use, thereby reducing the occupied area for product storage and facilitating the replacement of any damaged component (the puncture sheath 2 or the tube body 1).

[0043] For the seal proposed in the second implementation manner, in this embodiment, the seal can be a water-stop tape. The water-stop tape is wrapped around the external thread 14 and then screwed into the internal thread 22 to achieve the sealing of the thread; this method is known to those skilled in the art, such as the thread sealing of a faucet, and will not be elaborated in this specification. Alternatively, the seal can be a sealing ring 8. An annular pressing block 7 is fixedly provided on the outer surface of the tube body 1, and the axis of the annular pressing block 7 is collinear with the axis of the tube body 1. The sealing ring 8 is fixed on the annular pressing block 7. After the external thread 14 and the internal thread 22 are screwed together, the sealing ring 8 can be pressed between the annular pressing block 7 and the end face of the branch pipe 21 to achieve sealing.

[0044] In a feasible implementation manner, a second valve 6 is provided on the branch pipe 21 or the tube body 1 to control whether cerebrospinal fluid enters or exits the tube body 1; specifically, during pressure measurement, the first valve 5 is closed and the second valve 6 is opened, and cerebrospinal fluid can enter the tube body 1 for pressure measurement; when collecting cerebrospinal fluid, the second valve 6 can be closed and the first valve 5 can be opened to collect cerebrospinal fluid and prevent the cerebrospinal fluid in the tube body 1 from flowing out.

[0045] The present invention is not limited to the foregoing specific embodiments. The present invention extends to any new feature or any new combination disclosed in this specification, as well as to any new method or process step or any new combination disclosed.

Claims

1. A pressure measuring tube for lumbar puncture, characterized in that: The invention comprises a tube body (1), one end of the tube body (1) being a liquid inlet (11) for cerebrospinal fluid to enter the tube body (1), and the other end of the tube body (1) being a connecting port (12) for connecting the inside of the tube body (1) with the outside air; an elastic film (3) for isolating the connection between the connecting port (12) and the liquid inlet (11) is arranged inside the tube body (1), and the elastic film (3) has elasticity; and pressure scales (13) are marked on the tube body (1) from the position where the tube body (1) and the elastic film (3) are connected to the connecting port (12), and the pressure value of the pressure scale (13) is larger the closer to the connecting port (12).

2. The pressure measuring tube according to claim 1, characterized in that: A pointer (4) for indicating a pressure scale (13) is fixed on one side of the elastic film (3) facing the communication port (12), and the pointer (4) is slidably connected to the inner wall of the tube body (1).

3. The pressure measuring tube according to claim 2, characterized in that: The pointer (4) is clearance-matched with the inner wall of the tube body (1).

4. The pressure measuring tube according to claim 1, characterized in that: A sealant is used to achieve a sealed connection between the elastic film (3) and the tube body (1); or the tube body (1) comprises a first section (15) and a second section (16) which are sealedly connected by a flange (9), the flange (9) of the first section (15) is provided with a groove (92), and the flange (9) of the second section (16) is provided with a convex ring (91) matching the groove (92), and after the first section (15) and the second section (16) are connected, the convex ring (91) is located in the groove (92) and clamps the outer side of the elastic film (3).

5. A puncture tool, characterized in that: The invention comprises a puncture sheath (2) and a pressure measuring tube for lumbar puncture according to any one of claims 1 to 4, wherein the liquid inlet (11) is sealed and fixedly connected to the middle of the puncture sheath (2), and the liquid inlet (11) is connected to the inside of the puncture sheath (2); a first valve (5) is provided on the puncture sheath (2), and the installation position of the first valve (5) is located between the position where the puncture sheath (2) is connected to the liquid inlet (11) and the liquid outlet of the puncture sheath (2).

6. The puncture tool according to claim 5, characterized in that: The tube body (1) at the liquid inlet (11) is provided with a connection portion for sealingly connecting with the puncture sheath (2).

7. The puncture tool according to claim 6, characterized in that: The connecting portion is the end surface of the tube body (1), and the end surface of the tube body (1) is sealed and fixedly connected to the puncture sheath (2).

8. The puncture tool according to claim 6, characterized in that: A branch tube (21) is provided in the middle of the puncture sheath (2), and an internal thread (22) is provided on the inner wall of the branch tube (21); the connecting portion is an external thread (14) provided on the outer surface of the tube body (1), and the external thread (14) can be threadedly connected to the internal thread (22); a sealing member is provided between the tube body (1) and the branch tube (21).

9. The puncture tool according to claim 8, characterized in that: The sealing member is a water-stopping tape, which is wrapped around the external thread (14); or the sealing member is a sealing ring (8), an annular pressing block (7) is fixed to the outer surface of the tube body (1), and the sealing ring (8) is fixed on the annular pressing block (7), and the sealing ring (8) can be pressed between the annular pressing block (7) and the end face of the branch pipe (21).

10. The puncture tool according to claim 8, characterized in that: A second valve (6) is provided on the branch pipe (21) or the pipe body (1).

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