A pressure sensor filling needle

Abstract

The present application belongs to the field of medical devices, and discloses a pressure sensor filling needle, which comprises a pressure sensor, a hollow guide wire connected with the pressure sensor, and the hollow guide wire is filled with incompressible liquid and is used to transmit pressure from a blood vessel to the pressure sensor in a hydraulic manner; the pressure sensor comprises a connecting membrane with a pressure-sensitive resistor, a pressure port, and a sensor shell, one side of the connecting membrane is connected with the liquid, and the other side is covered with gel; the sensor shell is installed in the pressure port; when the liquid is subjected to pressure from the blood vessel, the pressure is transmitted to the pressure sensor through the hollow guide wire; the change of the resistance value of the pressure-sensitive resistor membrane in the pressure sensor can be detected by the PCB connected to the pressure sensor to obtain the pressure information of the blood vessel. The present pressure sensor filling needle utilizes a hydraulic system and resistance measurement technology to transmit and measure pressure, and various measures are adopted to protect the device itself and prevent the liquid from escaping.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a pressure sensor filling needle. Background Technology

[0002] Pressure monitoring guidewires play a crucial role in the diagnosis and interventional treatment of coronary artery disease. They facilitate the monitoring of intravascular pressure and can easily pass through the patient's blood vessels, particularly the anatomy of the coronary arteries. If the diagnosis indicates the need for interventional treatment, the pressure monitoring guidewire can also be conveniently used as a lead for subsequent PTCA balloon / stent catheters. Internationally recognized pressure monitoring guidewires compatible with standard PTCA devices offer particular advantages.

[0003] While conventional pressure measurement guidewires have unique advantages, they also have some inherent drawbacks and limitations. First, the design and manufacture of guidewires compatible with PTCA 0.014 devices are complex, requiring solutions to measurement problems related to low signal-to-noise ratios, necessitating sophisticated signal processing electronics. Second, pressure measurement accuracy is affected by air bubbles within the guidewire, which can impact the speed and accuracy of internal pressure measurements. Finally, sterilization, maintaining aseptic properties, and preventing evaporation of these guidewires present significant challenges, all of which limit their use.

[0004] Therefore, it is necessary to improve the existing pressure measuring guide wire equipment to solve the technical problem of the difficulty in removing air bubbles in conventional pressure measuring guide wires. Summary of the Invention

[0005] The purpose of this invention is to provide a pressure sensor filling needle to solve the above-mentioned technical problems.

[0006] To achieve this objective, the present invention employs the following technical solution: a pressure sensor injection needle, comprising a pressure sensor and a hollow guide wire connected to the pressure sensor, wherein the hollow guide wire is filled with an incompressible liquid for transmitting pressure from the blood vessel to the pressure sensor in a hydraulic manner. The pressure sensor includes a connecting membrane with a pressure-sensitive resistor, a pressure port, and a sensor housing. One side of the connecting membrane is connected to the liquid, and the other side is covered with a gel. The sensor housing is installed inside the pressure port, wherein the pressure port is provided with a plug to prevent the proximal end of the hollow guidewire from penetrating the gel or damaging the connecting membrane.

[0007] Optionally, an O-ring is provided inside the inner hole of the pressure port to achieve a seal between the outer diameter of the guide wire and the inner hole.

[0008] The varistor of the connecting membrane is electrically connected to a PCB board, wherein the PCB board has a ventilation opening.

[0009] Optionally, a syringe filled with incompressible liquid may also be included.

[0010] Optionally, the hollow guidewire also includes an inner tube and an outer tube, wherein the inner tube is deployed inside the outer tube and is provided with a connector to secure the inner tube to the outer tube, wherein the proximal end of the outer tube is connected to an outer shell suitable for receiving the syringe.

[0011] Optionally, the hollow guidewire is introduced into the pressure port to form an air-filled cavity containing a gel surface and an incompressible liquid front end.

[0012] Optionally, the inner and outer tube structures form a sub-assembly and are connected to the housing via a sleeve that introduces the near end into the housing.

[0013] Optionally, a sensor filling needle, made of a cannula, is also included, the proximal end of which is connected to an outer shell suitable for receiving the syringe.

[0014] Optionally, the outlet port connects the inner cavity of the sleeve to a pressure reducing valve.

[0015] Optionally, the pressure reducing valve is a resilient sleeve mounted on the outlet port.

[0016] Optionally, the resilient sleeve is covered with a shielding tube to protect the outlet hole from bending and breakage.

[0017] Compared with existing technologies, this invention has the following advantages: In this system, a hollow guidewire is filled with incompressible liquid; when the liquid is subjected to pressure from a blood vessel, this pressure is transmitted through the hollow guidewire to a pressure sensor connected to it. The pressure sensor contains a pressure-sensitive resistor membrane, one side of which is exposed to hydraulic pressure, while the other side is exposed to the atmosphere and covered by a gel; when pressure is transmitted to this membrane, the membrane's physical morphology is affected, thereby changing its resistance value; this change can be detected by a PCB connected to the pressure sensor; after detecting the change in membrane resistance, the PCB converts it into an electronic signal and then transmits this signal to an external electronic system to obtain the blood vessel pressure information; the sensor housing installed at the pressure port is equipped with a plug to prevent the proximal end of the hollow guidewire from penetrating the gel or damaging the membrane, protecting stable operation in any application scenario. Furthermore, an O-ring is designed between the port and the guidewire to provide a sealing effect and ensure liquid flow between the pressure sensor and the hollow guidewire; this pressure sensor filling needle utilizes a hydraulic system and resistance measurement technology to transmit and measure pressure, and employs multiple measures to protect the device itself and prevent liquid leakage. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0020] Figure 1 This is one of the schematic diagrams of the pressure sensor filling needle in this embodiment; Figure 2 This is the second schematic diagram of the pressure sensor filling needle in this embodiment; Figure 3 This is the third schematic diagram of the pressure sensor filling needle in this embodiment; Figure 4 This is the fourth schematic diagram of the pressure sensor filling needle in this embodiment; Figure 5 The pressure sensor filling needle in this embodiment Figure 4 A magnified schematic diagram of the structure at point A; Figure 6 This is the fifth schematic diagram of the pressure sensor filling needle in this embodiment; Figure 7 This is the sixth schematic diagram of the pressure sensor filling needle in this embodiment; Figure 8 This is the seventh schematic diagram of the pressure sensor filling needle in this embodiment; Figure 9 This is the eighth schematic diagram of the pressure sensor filling needle in this embodiment; Figure 10 This is diagram nine of the pressure sensor filling needles in this embodiment; Figure 11 This is the tenth schematic diagram of the pressure sensor filling needle in this embodiment; Figure 12 This is 11th schematic diagram of the pressure sensor filling needle in this embodiment; Figure 13 This is diagram 12 of the pressure sensor filling needle in this embodiment; Figure 14 This is diagram thirteen of the pressure sensor filling needles in this embodiment; Figure 15 This is the fourteenth schematic diagram of the pressure sensor filling needle in this embodiment; Figure 16 This is schematic diagram 15 of the pressure sensor filling needle in this embodiment; Figure 17 This is schematic diagram sixteen of the pressure sensor filling needle in this embodiment; Figure 18 This is schematic diagram seventeen of the pressure sensor filling needle in this embodiment; Figure 19 This is the eighteenth schematic diagram of the pressure sensor filling needle in this embodiment; Figure 20 The pressure sensor filling needle in this embodiment Figure 19 A magnified view of part B. Detailed Implementation

[0021] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0022] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.

[0023] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0024] This invention provides a pressure sensor filling needle, which connects a hollow guidewire or catheter 1 to a pressure sensor 2. The hollow guidewire 1 is fully filled with incompressible liquid 3, and pressure is transmitted from the blood vessel to the sensor in a hydraulic manner.

[0025] The pressure sensor 2 typically consists of a diaphragm 21 equipped with a pressure-sensitive resistor located within a housing 22. One side of the diaphragm 21 is exposed to hydraulic pressure, while the other side is exposed to the atmosphere. The side exposed to pressure is covered by a gel 23, which transmits hydraulic pressure. The sensor also includes a printed circuit board 24, which connects to the pressure-sensitive component of the diaphragm 21. It can also be connected to external electronic systems. PCB24 has a vent 25.

[0026] The sensor housing 22 is placed within a pressure port 26, which is adapted to receive the proximal end 101 of the hollow guidewire 1. The port 26 has a plug 261 to prevent the proximal end 101 from penetrating the gel 23 or damaging the membrane 21.

[0027] An O-ring 27 is located inside the inner hole 262 of the port 26 to seal the gap between the outer diameter of the guide wire 102 and the hole 262.

[0028] like Figure 2 As shown, when the hollow guidewire 1 is introduced into port 26, the orifice 262, the surface of the gel 23, and the tip of the incompressible liquid 3 form an air-filled cavity 4. As detailed in the background section above, it is important to completely remove air bubbles before introducing the guidewire and sensor interface into the blood vessel.

[0029] The following sections will describe in detail an example of a sensor filling needle designed to fill a cavity with an incompressible liquid: Figure 3 The image shows a sensor filling needle 10. The filling needle 10 is made of an inner tube 11 disposed within an outer tube 12. The inner diameter of the inner tube 11 is smaller than the difference between the inner diameter 121 of the outer tube 12 and the outer diameter 112 of the inner tube 11. In other words, the hydraulic diameter of the liquid passage within the inner tube 11 is smaller than the hydraulic diameter of the liquid passage within the outer tube 12.

[0030] Therefore, the flow resistance within the inner tube 11 is greater than the flow resistance within the outer tube 12. Note that, under normal circumstances, the ratio between the flow resistances is equal to the fourth power of the ratio between the hydraulic diameters. The proximal end 122 of the outer tube 12 is connected to an outer housing 13 (not shown) suitable for receiving a syringe. The outer tube 12 has an outlet port 123 connecting the inner diameter 121 of the outer tube 12 to the surrounding area.

[0031] The inner tube 11 is secured to the outer tube 12 via a connector 14 located near the outlet port 123. The connector 14 is formed by means such as brazing, adhesive, or welding. The connector 14 seals the inner diameter 121 of the outer tube 12, thereby blocking the direct liquid passage between the outer casing 13 and the outlet port 123.

[0032] The inner tube 11 is deployed inside the outer tube 12, such that the distal end 113 of the inner tube 11 protrudes beyond the distal end 124 of the outer tube 12.

[0033] like Figure 4 , Figure 5 As shown, a syringe 5 filled with incompressible liquid is connected to the housing 13. The outer tube 12 of the sensor filling needle 10 is inserted into the connector portion 26 until the distal end 124 of the outer tube 12 meets the stopper 261. In this position, the distal end 113 of the inner tube 11 extends into the sensor housing 22 until it reaches the side of the surface of the gel 23.

[0034] When injection is performed using syringe 5, incompressible liquid flows from syringe 5 through the inner tube to pressure sensor 2. Because the distal end 124 is in close proximity to gel 23, the incompressible liquid squeezed out of the inner tube 11 pushes air from the cavity 4 to the outlet port 123, thus completing the filling process for sensor 2. Injection continues, and incompressible liquid drips from the outlet port 123. The user sees these drops and knows that the filling process is complete.

[0035] Most of the pressure that causes the liquid to expel air 4 from the chamber drops between the syringe 5 and the sensor chamber 4 because the flow resistance of the inlet channel in the inner tube 11 is much higher than the flow resistance of the outlet channel in the outer tube 12. Therefore, the pressure drop between the sensor chamber 4 and the atmosphere is also very small, far below the overpressure limit of the sensor 2.

[0036] After filling is complete, the sensor filling needle 10 is removed. Now, as... Figure 6 As shown, the sensor cavity 4 is filled with incompressible liquid. In this state, the sensor is ready to receive the pre-filled guidewire 1. Figure 7 As shown, when the filling guide wire 1 is received into the sensor 2, there are no air bubbles.

[0037] exist Figure 8 It shows Figure 2 The preferred configuration for the sensor filling needle 10 is as follows: In this configuration, the outer tube 12 consists of two tubes: a short, thin distal tube 12a extending into a thick, long proximal tube 12b, which is retractable. These two tubes are joined together 125 by means such as brazing, adhesive, or welding. An outlet port 123 is located on the proximal tube 12b.

[0038] The distal tube 12a is long enough to be received within the connection portion 26 of the sensor 2. It is typically a few millimeters long. The diameter of the distal tube 12a is similar to the diameter of the hollow guide wire 1, typically 0.014 x 0.35 mm.

[0039] The proximal tube 12b is much longer and thinner. Generally, it is limited by the geometry of the components, devices, or systems consisting of sensors, for example, an outer diameter of 0.6 mm × an inner diameter of 0.4 mm × a length of 60 mm.

[0040] An inner tube 11 is deployed within the outer tube 12. The inner tube 11 is deployed within the outer tube 12 such that the distal end 113 of the inner tube 11 protrudes beyond the distal end 124 of the outer tube 12. The length of the inner tube causes its proximal end 114 to also protrude beyond the proximal end 122 of the proximal tube 12b.

[0041] These tubes are secured together by connectors 14 located at the proximal ends 122, 114. Connectors 14 seal the inner diameter 121 of the outer tube 12, thereby blocking the direct liquid passage between the outer casing 13 and the outlet port 123.

[0042] The inner tube 11 and the outer tube 12 form a sub-assembly. The sub-assembly is connected to the housing 13 by a sleeve 131 that is introduced into the housing 13 through the proximal ends 11, 12, 14, and then the sleeve 131 is connected to the adjacent proximal sub-assembly.

[0043] Figure 8 configuration ratio Figure 3 This configuration has several advantages. These advantages include the following: First, in Figure 8 In this configuration, not only is the hydraulic diameter of the inlet channel smaller than that of the outlet channel, but the length of the inlet channel is also much longer because the inner tube 11 is much longer than the distal portion 12b of the outer tube 12. This, in turn, increases the hydraulic resistance of the inner tube 11 relative to the outer tube 12.

[0044] Secondly, it should be noted that the diameter of the hollow guidewire is typically only 0.35mm thick, with a configuration ratio of thick proximal tube. Figure 3 The configuration is more robust. Third, the assembly process is much easier if the connection is made at the proximal end, rather than through the orifice of the outer tube 12.

[0045] In the following sections, another example of a sensor filling needle designed to fill a cavity with an incompressible liquid will be described in detail: In this method using a filling needle, air is evacuated from sensor cavity 4 and water is injected through a vacuum. In this example, the filling needle consists of a cannula, a syringe, and a pressure reducing valve. The syringe is filled with a small amount of water.

[0046] A side port in the sleeve is connected to a pressure-reducing valve, 25 to protect the sensor. The pressure-reducing valve is adjusted to open at a threshold pressure well below the sensor's overpressure limit.

[0047] Figure 9 The image shows a sensor filling needle 100. The filling needle 100 is made of a cannula 1010. The proximal end 1011 of the cannula 1010 is connected to a housing 13 (not shown) suitable for receiving a syringe.

[0048] The sleeve 1010 has an outlet port 1013. The outlet port 1013 connects the inner cavity 1012 of the sleeve 1010 to the pressure reducing valve 1020.

[0049] An example of this pressure-reducing valve is a resilient sleeve 1020 installed on the outlet port. For example... Figure 20 As shown in the detailed diagram, if the pressure inside sleeve 1010 exceeds a threshold, liquid water will leak from between the sleeve and the outer surface 1014 of sleeve 1010. Sleeve 1020 is made of an elastomeric material, such as soft silicone rubber or TPU. The threshold depends on the size of the sleeve and its material properties. Because sleeve 1020 is softer and has a thinner wall, the fit between the sleeve and the tube is looser, resulting in a lower leakage threshold. Conversely, the larger the sleeve, the thinner its wall, and the looser the fit between the sleeve and the tube, the lower the leakage threshold.

[0050] In this example, the flexible sleeve 1020 is covered by a shielding tube 1030, which protects the weakest part of the sleeve 1010, the outlet port 1013, from bending and breaking. The shielding tube 1030 prevents the user from accidentally contacting the flexible sleeve.

[0051] like Figure 10 As shown, a syringe 5 filled with incompressible liquid is connected to the outer casing 13. Figure 11 As shown, when filling the sensor cavity 4, the distal end 1015 of the sleeve 1010 is inserted into the pressure port 26 of the sensor 2 until the distal end 124 of the outer tube 12 meets the plug 261.

[0052] like Figures 12 to 18 As shown, the filling of the handle is performed in the following order: like Figure 12 As shown, pressing the syringe piston 51 causes air to fill the syringe 5, outer shell 13, and cannula 1010. like Figure 13 As shown, the filling needle 100 is connected to the pressure port 26 of the sensor 2 until the distal end 1015 meets the plug 261. In a suggested configuration, the sensor has a locking mechanism, such as a collet and a locking nut (not shown), to lock the position of the filling needle 10 or the guide wire 1. Figure 14 As shown, pulling piston 51 creates a vacuum inside syringe 5. Simultaneously with applying a vacuum to gas chamber 4, its volume expands rapidly. This expansion is determined by the ratio between atmospheric pressure (1 atm) and the absolute vacuum pressure.

[0053] For example, if a vacuum in a syringe results in an absolute pressure of 0.01 atm, the volume of the cavity will be 100 times larger than the volume under atmospheric conditions.

[0054] like Figure 15As shown, as piston 51 is pulled up, syringe 5 is rotated to make it vertical with the tip pointing downwards. When the syringe is held vertically with the tip pointing downwards, bubble 41... It rises under the influence of buoyancy. For example... Figure 16 As shown, wait at this position until bubble 41 stops moving from cannula 1010 into syringe 5.

[0055] like Figure 17 As shown, piston 51 is slowly released. After the piston is released, the pressure inside the syringe rises from vacuum to atmospheric pressure. As the pressure increases, the amount of air 42 remaining in the chamber is compressed to a negligible volume. like Figure 18 As shown, loosen the set nut and remove the filling needle. Now, as... Figure 6 As shown, the sensor cavity 4 is filled with incompressible liquid. In this case, the sensor is ready to receive the filled guide wire 1. Figure 7 As shown, when the filling guide wire 1 is received into the sensor 2, there are no related air bubbles.

[0056] like Figure 19 , Figure 20 As shown, if the syringe piston 51 is pressed and the pressure of the sensor, cannula and syringe exceeds the threshold, water 3 will overflow from the pressure reducing valve 1020 to prevent the sensor from being exposed to overpressure.

[0057] The innovative device described in this article improves the filling process of a hydraulic measurement system, including a pressure sensor and a hollow guide wire or conduit.

[0058] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pressure sensor filling needle, characterized in that, Includes a pressure sensor (2), a hollow guide wire (1) connected to the pressure sensor (2), the hollow guide wire (1) being filled with an incompressible liquid (3) for hydraulically transmitting pressure from the blood vessel to the pressure sensor (2). The pressure sensor (2) includes a connecting membrane (21) with a pressure-sensitive resistor, a pressure port (26) and a sensor housing (22). One side of the connecting membrane (21) is subjected to the hydraulic pressure transmitted by the liquid (3), and the other side is in communication with the atmosphere. The side subjected to the hydraulic pressure is covered by a gel (23). The sensor housing (22) is installed inside the pressure port (26), wherein the pressure port (26) is provided with a plug (261) to prevent the proximal end (101) of the hollow guidewire (1) from penetrating the gel (23) or damaging the connecting membrane (21). It also includes a syringe (5) filled with incompressible liquid. The pressure sensor filling needle also includes an inner tube (11) and an outer tube (12), wherein the inner tube (11) is deployed inside the outer tube (12) and is provided with a connector (14) to fix the inner tube (11) to the outer tube (12). The proximal end (122) of the outer tube (12) is connected to an outer shell (13) suitable for receiving the syringe (5), and the syringe (5) is connected to the outer shell (13). The inner diameter of the inner tube (11) is smaller than the difference between the inner diameter (121) of the outer tube (12) and the outer diameter (112) of the inner tube (11), and the hydraulic diameter of the liquid channel in the inner tube (11) is smaller than the hydraulic diameter of the liquid channel in the outer tube (12). The outer tube (12) is provided with an outlet hole (123), which connects the inner diameter (121) of the outer tube (12) to the surrounding area; The inner tube (11) is fixed to the outer tube (12) by the connector (14) located near the outlet hole (123), the connector (14) sealing the inner diameter (121) of the outer tube (12), thereby blocking the direct liquid passage between the outer shell (13) and the outlet hole (123); The distal end (113) of the inner tube (11) protrudes beyond the distal end (124) of the outer tube (12), which is inserted into the pressure port (26) until the distal end (124) of the outer tube (12) meets the plug (261). At this position, the distal end (113) of the inner tube (11) extends into the sensor housing (22) until it is next to the surface of the gel (23).

2. The pressure sensor filling needle according to claim 1, characterized in that, An O-ring (27) is provided inside the inner hole (262) of the pressure port (26) to achieve a seal between the outer diameter of the hollow guide wire (1) and the inner hole (262); The varistor of the connecting film (21) is electrically connected to the PCB board (24), wherein the PCB board (24) has a vent (25).

3. The pressure sensor filling needle according to claim 1, characterized in that, The hollow guide wire (1) is inserted into the pressure port (26) to form an air-filled cavity (4) containing a surface of gel (23) and a front end of incompressible liquid (3).

4. The pressure sensor filling needle according to claim 1, characterized in that, The inner tube (11) and outer tube (12) structure form a sub-assembly, the proximal end of which is inserted into the sleeve (131) of the outer shell (13) and connected to the outer shell (13) through the sleeve (131).

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