Force sensing guide wire

Abstract

The present disclosure relates to a force sensing guidewire comprising: a tubular member; the head end cap is connected with the tubular component; the hole is formed in the head end cap and extends to the far side end of the head end cap, and the included angle between the extending direction of the hole and the axial direction of the head end cap is smaller than 30 degrees; a pressure sensor disposed adjacent a proximal end of the aperture; and the flexible part is made of a gel or silica gel material, is arranged on the pressure sensor, and extends to the far side end of the head end cap in the hole. The force sensing guidewire of the present disclosure can measure both blood pressure and contact force between the force sensing guidewire and a tissue wall.

Description

Technical Field

[0001] The present disclosure relates to a force sensing guidewire. Background Art

[0002] Force-sensing guidewires can be used for minimally invasive interventional diagnosis and treatment in both vascular and non-vascular cavities. One force-sensing guidewire configuration includes a sensor housing positioned between a mid-portion and a distal portion, housing a pressure sensor within the housing, and providing a window for sensing external pressure. However, the inventors discovered that this approach fails to monitor the contact force between the force-sensing guidewire and the tissue wall, and collision with the tissue wall can result in damage to the vessel or organ wall. Summary of the Invention

[0003] Therefore, an object of the present disclosure is to provide a force sensing guidewire that can measure both blood pressure and contact force with a tissue wall.

[0004] The above objects are achieved by a force sensing guidewire according to the following description.

[0005] The present disclosure relates to a force sensing guidewire, comprising: a tubular member; a head end cap connected to the tubular member; a hole arranged in the head end cap and extending to the distal end of the head end cap, wherein the angle between the extension direction of the hole and the axial direction of the head end cap is less than 30 degrees; a pressure sensor arranged at the proximal end adjacent to the hole; and a flexible portion made of gel or silicone material, arranged on the pressure sensor, and extending in the hole to the distal end of the head end cap.

[0006] In one embodiment, the proximal end of the aperture is located within the tip cap, and the tip cap includes a proximal end wall.

[0007] In one embodiment, an optical fiber connected to the pressure sensor extends through the proximal end wall of the tip cap toward the tubular member.

[0008] In one embodiment, the hole extends along the axial direction of the tip cap to the distal end of the tip cap.

[0009] In one embodiment, the hole comprises a through hole extending through the head end cap.

[0010] In one embodiment, the method further comprises a supporting component for fixing the pressure sensor, wherein the supporting component is located in the hole or in the tubular member.

[0011] In one embodiment, the distal end portion of the tubular member includes a developing spring connected to the head end cap, and a head end core wire nested in the developing spring.

[0012] In one embodiment, the aperture of the hole increases in a direction extending toward the distal end of the tip cap.

[0013] In one embodiment, the pressure sensor is disposed within the hole.

[0014] In one embodiment, it also includes an optical fiber, which extends inside the tubular member, and the pressure sensor is arranged at the end of the optical fiber; a Bragg grating for measuring the bending direction of the force feedback guide wire is provided on the optical fiber, and a sensing plate is provided on one side of the Bragg grating.

[0015] The present disclosure also provides a method for preparing a force sensing guidewire, comprising: opening a hole in a head cap, the hole extending to the distal end of the head cap; fixing a pressure sensor at a proximal end adjacent to the hole; filling liquid silicone or gel into the hole, heating and curing it to form a flexible portion, the flexible portion extending to the distal end of the head cap.

[0016] The present disclosure has the following advantages: the contact force between the blood pressure or force sensing guidewire and the tissue wall can be transmitted to the pressure sensor via the flexible portion, and the force sensing guidewire can measure both the blood pressure and the contact force between the force sensing guidewire and the tissue wall. When the force sensing guidewire is not in contact with the tissue wall, the blood pressure can be transmitted to the pressure sensor via the flexible portion, thereby measuring the blood pressure; when the force sensing guidewire is in contact with the tissue wall, the contact force applied to the tip of the force sensing guidewire can be transmitted to the pressure sensor via the flexible portion, thereby measuring the contact force applied to the force sensing guidewire. This eliminates the need to replace medical equipment, making operation convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings of the embodiments of the present disclosure. The drawings are only used to illustrate some embodiments of the present disclosure, and are not intended to limit all embodiments of the present disclosure to these drawings.

[0018] Figure 1 A schematic structural diagram of a force sensing guidewire according to an embodiment of the present disclosure is shown;

[0019] Figure 2 A schematic structural diagram of a force sensing guidewire according to another embodiment of the present disclosure is shown.

[0020] 1- Tubular member 12- Distal end portion 121- Development spring 122- Tip end core wire 2- Tip end cap 21- Proximal end wall of tip end cap 22- Distal end of tip end cap 23- Axial direction of tip end cap 3- Hole 31- Proximal end of hole 4- Pressure sensor 5- Flexible portion 6- Support member 7- Optical fiber 8- Channel DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the technical solution of the present disclosure clearer, the technical solution of the embodiment of the present disclosure will be clearly and completely described below in conjunction with the drawings of the specific embodiments of the present disclosure. The same figure marks in the drawings represent the same parts. It should be noted that the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0022] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by persons of ordinary skill in the field to which the present disclosure belongs. The words "first", "second" and similar terms used in the patent application specification and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "a" or "an" do not necessarily indicate a quantity limitation. Words such as "include", "comprise" or "have" mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connected" or "connected" are not limited to the physical or mechanical connections or connections shown in the drawings, but may include equivalent connections or connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0023] Some medical interventions require monitoring blood pressure within blood vessels. For example, some medical devices can include pressure sensors that allow clinicians to monitor blood pressure. Such devices can be used to determine the fractional flow reserve, which can be understood as the ratio of the pressure after stenosis to the pressure before stenosis. The inventors of the present disclosure have discovered that medical devices that only monitor blood pressure and fail to measure contact force with the vessel wall can cause damage to the vessel wall or organ wall when the medical device collides with the vessel wall, while also causing operational inconvenience.

[0024] Reference below Figures 1 to 2 Embodiments of a force sensing guidewire according to the present disclosure are described in detail.

[0025] In one embodiment of the present disclosure, a force sensing guidewire includes: a tubular member 1; a head end cap 2, which is connected to the tubular member 1; a hole 3, which is arranged in the head end cap 2 and extends to the distal end 22 of the head end cap, and the angle between the extension direction of the hole 3 and the axial direction 23 of the head end cap is less than 30 degrees; a pressure sensor 4, which is arranged at the proximal end 31 adjacent to the hole; a flexible portion 5, made of gel or silicone material, is arranged on the pressure sensor 4, and extends in the hole 3 to the distal end 22 of the head end cap.

[0026] A flexible portion 5 made of a gel or silicone material is disposed on the pressure sensor 4. Blood pressure or contact force with the tissue wall can be transmitted to the pressure sensor 4 through the flexible portion 5. The pressure sensor 4 can sense the force and transmit the signal to a display or monitoring device (not shown). When the force sensing guidewire is not in contact with the tissue wall, the blood pressure can be transmitted to the pressure sensor through the flexible portion, thereby measuring the blood pressure. When the force sensing guidewire is in contact with the tissue wall, the contact force applied to the tip of the force sensing guidewire can be transmitted to the pressure sensor through the flexible portion, thereby measuring the contact force applied to the force sensing guidewire. In this way, both blood pressure and contact force with the tissue wall can be sensed without the need to replace medical equipment, making operation convenient.

[0027] The tubular member 1 can be made of any material, such as medical grade 304V stainless steel. The tubular member can have any length, such as 1800 mm, an outer diameter of no more than 0.36 mm, such as 0.355 mm, and an inner diameter of between 0.13 mm and 0.18 mm.

[0028] The tubular member 1 can be integrally formed from the same material, or can be welded from two or more segments. In some embodiments, the tubular member 1 includes a proximal portion and a distal portion 12. The proximal portion is divided into a slender tubular structure. During the diagnosis and treatment process, part of it is located outside the body. The operator manipulates the force sensing guide wire through the proximal portion to make it move along the blood vessels or non-vascular cavities of the human body. The distal portion 12 of the tubular member 1 includes a developing spring 121 and a head end core wire 122 nested in the developing spring 121. The distal portion and the proximal portion can be connected by a connector. The connector is a cylindrical structure with thin ends and a thick middle. One end of the connector is inserted into the developing spring and the other end is inserted into the proximal portion. The head end core wire 122 can be fixed to the connector.

[0029] The outer diameter of the end cap 2 is substantially the same as that of the tubular member 1 and may be no greater than 0.36 mm, for example, 0.355 mm. The length of the end cap may be 1.5 mm to 3 mm, for example, 2 mm. The material of the end cap is not limited and may be stainless steel, for example, medical-grade 304V stainless steel.

[0030] The hole 3 is provided in the head end cap 2 and extends to the distal end 22 of the head end cap. The position of the hole 3 in the head end cap 2 is not limited. In some embodiments, the center of the hole 3 is adjacent to the axis of the head end cap 2. The hole 3 is a strip-shaped hole along the extension direction. The cross-sectional shape of the hole 3 may include a circle, and may also include but is not limited to other shapes such as a polygon and a cross. The aperture of the hole 3 may be the same or different at different positions in the extension direction. In some embodiments, the aperture of the hole 3 gradually increases along the extension direction toward the distal end 23 of the head end cap to improve the force sensing sensitivity of the force sensing guide wire.

[0031] The angle between the extension direction of the hole 3 and the axial direction 23 of the head end cap is less than 30 degrees. In some embodiments, the hole 3 extends along the axial direction 23 of the head end cap to the distal end 22 of the head end cap to enhance the sensitivity of the force sensing guide wire to the axial force in contact with the tissue wall.

[0032] In some embodiments, the proximal end 31 of the hole is located within the head cap 2, the length of the hole 3 is less than the length of the head cap 2, and the head cap includes a proximal end wall 21 located at the proximal end 31 of the hole. The pressure sensor 4 can be set on the proximal end wall 21 to avoid the risk of the pressure sensor falling off and improve the sensing sensitivity. The length of the hole is not limited, for example, it can be 1mm-1.5mm. In some embodiments, a channel 8 for the passage of the optical fiber 7 can be provided on the proximal end wall 21 of the head cap. The optical fiber 7 is connected to the pressure sensor 4 and extends toward the tubular member 1 through the channel 8. The aperture of the channel 8 is larger than the outer diameter of the optical fiber. In some embodiments, the hole 3 is a through hole that passes through the head cap 2 along the axial direction 23 of the head cap, and the length of the hole 3 is approximately equal to the length of the head cap 2. A glue dispensing hole for gluing the pressure sensor 4 can be provided on the side wall of the head cap 2. The end of the head core wire 122 can be located in the channel 8 to prevent the head core wire from touching the tissue wall.

[0033] In some embodiments, the hole 3 is a through hole that passes through the head end cap 2 along the axial direction 23 of the head end cap. The pressure sensor 4 can be arranged in the hole 3, or it can be arranged in whole or in part in the tubular member 1. The pressure sensor 4 can be fixed on the side wall of the hole 3, or it can be fixed on the support component 6, and the fixing method includes but is not limited to pasting, welding, clamping and the like. The sum of the lengths of the pressure sensor 4 and the flexible portion 5 can be less than the length of the head end cap 2, or it can be greater than or equal to the length of the head end cap. The support component 6 for supporting the pressure sensor 4 can be arranged in the tubular member 1 or in the hole 3. The material of the support component 6 is not limited, for example, it can include stainless steel, and the support component 6 can be fixed to the tubular member 1 or the hole 3 by, for example, bonding, welding and the like. The end of the head end core wire 122 can be located in the hole 3 to prevent the head end core wire from touching the tissue wall.

[0034] In some embodiments, the pressure sensor 4 is disposed within the aperture 3. The length of the flexible portion 5 and the pressure sensor 4 is not limited, and the sum of the lengths of the flexible portion 5 and the pressure sensor 4 is no greater than the length of the aperture 3. This protects the pressure sensor from external impact and reduces the risk of the pressure sensor falling off. The length of the pressure sensor can be no greater than 0.3 mm. The method of securing the pressure sensor 4 within the aperture 3 is not limited. For example, the pressure sensor 4 can be secured to the proximal end wall 21 of the head cap, to the sidewall of the aperture 3, or to the support member 6.

[0035] The pressure sensor 4 may include a semiconductor (e.g., silicon wafer) pressure sensor, a piezoelectric pressure sensor, an optical fiber or optical pressure sensor, a Fabry-Perot pressure sensor, an ultrasonic transducer and / or an ultrasonic pressure sensor, a magnetic pressure sensor, a solid-state pressure sensor, or any other suitable pressure sensor. In some embodiments, a flexible portion is provided on the pressure sensing surface of the pressure sensor, and a surface of the pressure sensor opposite the pressure sensing surface is connected to an optical fiber 7, which extends into the tubular member 1.

[0036] The flexible portion 5 extends within the hole 3 to the distal end 22 of the head cap, and is defined as being flush with the end surface of the distal end 22 of the head cap, or being slightly higher than the end surface of the distal end 22 of the head cap, so that the force applied to the head cap 2 is transmitted to the pressure sensor 4 through the flexible portion, and the pressure sensor 4 changes in response to the change in the force applied to the head cap 2. The pressure sensor 4 and the flexible portion 5 can be integrally formed or provided separately. The flexible portion can be formed by filling liquid silicone or gel into the hole 3 in which the pressure sensor 4 is fixed, and heating and curing it. The outer diameter of the flexible portion 5 is approximately equal to the aperture of the hole 3.

[0037] The aperture 3 at the location accommodating the pressure sensor 4 can have the same or different diameters as the aperture at the location accommodating the flexible portion 5. In some embodiments, the aperture at the location accommodating the pressure sensor 4 is larger than the aperture at the location accommodating the flexible portion 5. The aperture at the location accommodating the pressure sensor 4 is slightly larger than the outer diameter of the pressure sensor 4 to accommodate the pressure sensor. For example, the aperture at the location accommodating the flexible portion 5 can have a diameter of 0.1 mm to 0.3 mm, such as approximately 0.25 mm, while the aperture at the location accommodating the pressure sensor 4 can have a diameter greater than 0.26 mm.

[0038] In one embodiment, the force feedback guide wire also includes an optical fiber, which extends within the tubular member, and the pressure sensor is arranged at the end of the optical fiber; a Bragg grating for measuring the bending direction of the force feedback guide wire is provided on the optical fiber, and a sensing plate is provided on one side of the Bragg grating.

[0039] The length of the Bragg grating is not limited, for example, it can be 1mm, 2mm, or 5mm. The material and shape of the sensing sheet are not limited, and the sensing sheet can include a metal sheet such as an aluminum sheet. The sensing sheet can be set on one side of the Bragg grating by gluing or the like. The length of the sensing sheet can be equivalent to the grating area length of the Bragg grating, and the length of the sensing sheet can be set to 0.5-1.5 times the grating area length of the Bragg grating. The width of the sensing sheet can be not less than the diameter of the optical fiber. When the force sensing guide wire bends toward the sensing sheet, the optical fiber Bragg grating is compressed, and the central wavelength of the corresponding grating output decreases. When the force sensing guide wire bends away from the sensing sheet, the optical fiber Bragg grating is stretched, and the central wavelength of the corresponding grating output increases. Therefore, the bending direction of the force feedback guide wire can be measured, thereby realizing the determination of the bending direction of the force sensing guide wire. At the same time, the pressure sensor set at the end of the optical fiber can measure the blood pressure or the contact force between the force feedback guide wire and the tissue wall.

[0040] The present disclosure provides a method for preparing a force-sensing guidewire, comprising: opening a hole in a tip cap, the hole extending to the distal end of the tip cap; securing a pressure sensor proximal to the hole; and filling the hole with liquid silicone or gel, heating and curing it to form a flexible portion, the flexible portion extending to the distal end of the tip cap. The force-sensing guidewire prepared by this method can sense both blood pressure and contact force with tissue walls, without requiring replacement of medical equipment, and is easy to operate.

[0041] In addition, the technical features disclosed above are not limited to the disclosed combinations with other features. Those skilled in the art may also make other combinations between the technical features according to the purpose of disclosure to achieve the purpose of this disclosure.

Claims

1. A force sensing guidewire, characterized in that: include: Tubular components; a head end cap connected to the tubular member; a hole disposed in the head end cap and extending to the distal end of the head end cap, wherein the angle between the extending direction of the hole and the axial direction of the head end cap is less than 30 degrees; a pressure sensor disposed adjacent the proximal end of the aperture; The flexible portion is made of gel or silicone material, is disposed on the pressure sensor, and extends within the hole to the distal end of the head cap.

2. The force sensing guidewire according to claim 1, wherein: A proximal end of the aperture is located within the tip cap, which includes a proximal end wall.

3. The force sensing guidewire according to claim 2, wherein: An optical fiber connected to the pressure sensor extends toward the tubular member through the proximal end wall of the head cap.

4. The force sensing guidewire according to claim 1, wherein: The hole extends along the axial direction of the tip cap to the distal end of the tip cap.

5. The force sensing guidewire according to claim 1, wherein: The hole comprises a through hole extending through the head end cap.

6. The force sensing guidewire according to claim 5, characterized in that The device further comprises a supporting component for fixing the pressure sensor, wherein the supporting component is located in the hole or in the tubular member.

7. The force sensing guidewire according to claim 1, wherein: The tubular component includes a developing spring connected to the head end cap and a head end core wire nested in the developing spring.

8. The force sensing guidewire according to claim 1, wherein: The hole diameter increases along a direction extending toward the distal end of the head end cap.

9. The force sensing guidewire according to claim 1, wherein: The pressure sensor is disposed in the hole.

10. The force sensing guidewire according to claim 1, wherein: It also includes an optical fiber, which extends inside the tubular member, and the pressure sensor is arranged at the end of the optical fiber; a Bragg grating for measuring the bending direction of the force sensing guide wire is arranged on the optical fiber, and a sensing plate is arranged on one side of the Bragg grating.

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