Medical guide wire and medical system

Abstract

The utility model provides a medical guide wire and a medical system. The medical guide wire comprises a far-end part and a pushing rod which are sequentially connected from far to near in the axial direction of the medical guide wire. The pushing rod is provided with an inner hole extending in the axial direction in a penetrating mode. The far end part comprises at least one magnetic positioning sensor; the magnetic positioning sensor comprises a magnetic core and an induction coil wound on the outer surface of the magnetic core; at least two wires are led out from the induction coil, penetrate through an inner hole of the pushing rod and extend to the near end of the pushing rod. The medical system comprises a medical guide wire and a medical catheter; the medical catheter is provided with a guide wire passage which penetrates through the medical catheter in the axial direction of the medical catheter; the medical guide wire is used for movably penetrating through the guide wire passageway. By means of the configuration, visualization of the medical guide wire can be achieved, then visualization of the tissue structure and the medical catheter can be achieved through the medical guide wire, the passing ability of the catheter can be improved, the operation safety is improved, and the operation complexity is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to a medical guidewire with a three-dimensional magnetic positioning function, and a medical system comprising the medical guidewire and a medical catheter. Background Art

[0002] Interventional therapy is an emerging treatment method between surgical and medical treatment. Interventional therapy is a minimally invasive treatment method that creates tiny channels with a diameter of several millimeters in blood vessels or skin, or through existing channels in the human body, to treat local lesions under the guidance of imaging equipment (such as DSA, CT, MR, and B-ultrasound) without exposing the lesion through surgery. With the continuous aggravation of aging, the number of patients with cardiovascular and peripheral vascular diseases has continued to grow, and the demand for vascular interventional medical devices has continued to expand. Interventional surgery has been increasingly widely used in the diagnosis and treatment of malignant tumors, cardiovascular diseases, etc. due to its advantages of less trauma to the human body, short recovery time and low cost.

[0003] In the field of vascular interventional therapy, catheters and guidewires are essential consumables. Due to the fact that the shapes of human lumens such as the heart chambers, blood vessels and digestive tract are curved and changeable and even have many forks, it is difficult for the operator to push the catheter to the target position. Especially in the blind spots of blood vessels with a small radius of curvature, the operator needs to use X-ray machines or other imaging equipment to prevent safety issues such as path deviation and damage to blood vessels during the pushing process. The guidewire has the function of preliminary exploration and guidance, which helps to improve the placement of the catheter and the safety of operation. To this end, people have developed integral exchange catheters and rapid exchange catheters, that is, by combining an independently controllable guidewire with a separate catheter component, the guidewire is first passed through the narrow area of ​​the lumen to reach the target site, and then the catheter sheathed on the guidewire is introduced through the guidewire, so that the catheter is placed along the guidewire path, which greatly improves the operability and safety of clinical intraluminal interventional technology.

[0004] However, during the process of using a guidewire to switch catheters, there is displacement and vibration at the distal end of the guidewire, which can lead to vascular damage. Therefore, during the operation, it is still necessary to use imaging equipment to locate the guidewire and catheter and observe the vascular structure. In existing related technologies, some catheters are also equipped with three-dimensional magnetic positioning sensors to achieve three-dimensional magnetic positioning, thereby tracking the position and direction of the catheter. However, the main problem with the three-dimensional magnetic positioning sensors installed on existing catheters is their large size, especially since the distal end of the catheter needs to integrate many functions, which will greatly increase the design difficulty of the distal end of the catheter.

[0005] It should be noted that the information disclosed in the background technology section of this application is only intended to deepen the understanding of the general background technology of this application, and should not be regarded as an admission or any form of implication that the information constitutes prior art already known to those skilled in the art. Utility Model Content

[0006] The purpose of this application is to provide a medical guidewire and a medical system to solve the problem of vascular damage caused by displacement and vibration of the distal end of the guidewire during catheter switching using the guidewire in the existing related technology.

[0007] To achieve the above-mentioned objectives, the present application provides a medical guide wire, comprising: a distal portion and a push rod connected in sequence from far to near along its own axial direction; the push rod has an inner hole extending through along its own axial direction; the distal portion includes at least one magnetic positioning sensor; the magnetic positioning sensor includes a magnetic core and an induction coil wound on the outer surface of the magnetic core; the induction coil leads to at least two wires, and at least two of the wires pass through the inner hole of the push rod and extend to the proximal end of the push rod.

[0008] Optionally, the distal part also includes a head cap, a sheath structure and an internal structure; the head cap is fixed to the distal end of the sheath structure; the sheath structure is sleeved on the outside of the internal structure; the internal structure includes a core structure, the proximal end of the core structure is connected to the distal end of the push rod, and at least part of the core structure forms a magnetic core and is wound with the induction coil, and the induction coil leads out at least two of the wires at its proximal end.

[0009] Optionally, part of the structure of the core structure forms a magnetic core, and the core structure includes a magnetic core, a variable diameter section and a constant diameter section connected in sequence from far to near along its own axial direction; the proximal end of the constant diameter section is connected to the distal end of the push rod; the variable diameter section and the constant diameter section both have an inner hole extending through along their own axial direction; the inner hole of the variable diameter section, the inner hole of the constant diameter section and the inner hole of the push rod are connected in sequence; a part of the length of the magnetic core is embedded in the inner hole of the variable diameter section from the distal end of the variable diameter section and fixed; the outer diameter of the variable diameter section gradually increases from far to near throughout its entire length; the maximum outer diameter of the variable diameter section is the same as the outer diameter of the constant diameter section; the outer diameter of the constant diameter section is smaller than the outer diameter of the push rod; at least two of the wires extend from the distal end of the variable diameter section into the inner hole of the variable diameter section, and then extend along the inner hole of the variable diameter section, the inner hole of the constant diameter section and the inner hole of the push rod to the proximal end of the push rod.

[0010] Optionally, a conical transition section is provided between the proximal end of the core structure and the distal end of the push rod, and the outer diameter of the conical transition section gradually increases from far to near throughout its entire length.

[0011] Optionally, the entire structure of the core structure forms one magnetic core; or, part or all of the structure of the core structure forms multiple magnetic cores, and the multiple magnetic cores are distributed in sequence in the axial direction of the core structure, and an induction coil is wound around the outer surface of each magnetic core, and each induction coil is independent of each other, and each induction coil leads out at least two wires at its proximal end, and all the wires pass through the same inner hole of the push rod and extend to the proximal end of the push rod.

[0012] Optionally, the distal portion further includes a shaping structure, which is located inside the sheath structure and respectively connects the proximal end of the head cap and the distal end of the core structure.

[0013] Optionally, a rubber coating layer is provided on the entire outer surface of the conical transition section, the outer diameter of the rubber coating layer gradually increases from far to near, and the maximum outer diameter of the rubber coating layer is less than or equal to the outer diameter of the push rod.

[0014] Optionally, the head end cap is a developable structure, or the head end cap is a gel ball formed by gel production or a molten ball formed by melting.

[0015] Optionally, two wires are led out from any of the induction coils, and the two wires form a twisted pair structure.

[0016] Optionally, a socket is provided at the proximal end of the pushing rod, the induction coil is connected to the socket via at least two of the lead-out wires, and the socket can filter the induction signal output by the induction coil.

[0017] Optionally, a fastening position is provided at the proximal end of the push rod, and the distance from the fastening position to the distal end of the medical guide wire is the same as the distance from the distal end of the medical catheter to the proximal guide wire entrance; the medical guide wire is used to be detachably connected to the proximal end of the medical catheter at the fastening position; when the medical guide wire is connected to the medical catheter at the fastening position, the distal end portion is accommodated inside the distal end of the medical catheter.

[0018] Optionally, a positioning mark is provided at the fastening position; a conical transition section is provided at the distal end of the push rod, a first glue-coated section is provided on a part of the outer surface of the conical transition section along the circumferential direction, and a second glue-coated section is provided on the other part, the outer diameter of the first glue-coated section gradually decreases from far to near, and a bayonet is formed at the proximal end, and the second glue-coated section has a constant outer diameter from far to near; the positioning mark is provided on the same side as the first glue-coated section.

[0019] Optionally, the magnetic positioning sensor has at least one of the following features:

[0020] The outer surface of the magnetic core is provided with textures to accommodate the wire wound around the induction coil;

[0021] The length of the induction coil accounts for 75%-90% of the length of the magnetic core;

[0022] The wire diameter of the induction coil is 20 μm-30 μm;

[0023] The number of winding layers of the induction coil does not exceed 2 layers, and the number of winding turns of the induction coil does not exceed 280 turns;

[0024] The outer diameter of the magnetic core is 0.15mm-0.18mm, and the length of the magnetic core is 4mm-4.4mm;

[0025] The magnetic core is a solid structure or a hollow structure;

[0026] The magnetic core is made of amorphous material.

[0027] Optionally, the specification of the medical guide wire is 0.014 inch to 0.038 inch.

[0028] In addition, based on the same inventive concept, the present application also provides a medical system, which includes: a medical catheter and any one of the medical guidewires; the medical catheter has a guidewire passage arranged along its own axis; the medical guidewire is used to movably pass through the guidewire passage.

[0029] Optionally, the medical catheter includes a bendable section, and the guidewire passage includes a guidewire cavity disposed in the bendable section; a retraction limiter is disposed at a proximal end of the guidewire cavity; the retraction limiter has an initial state and a limit state, and is capable of switching between the initial state and the limit state;

[0030] In the initial state, the retraction limit portion can allow the distal end portion of the medical guide wire and the push rod to pass through;

[0031] In the limited state, the retraction limit portion is deformed after being subjected to the retraction force of the medical guide wire, thereby preventing the connection between the distal end of the medical guide wire and the push rod from passing through, so that the connection between the distal end of the medical guide wire and the push rod is limited in the retraction limit portion, thereby preventing the push rod from staying in the bendable section.

[0032] Optionally, the retraction limiting portion is an annular wall, one end of the annular wall is connected to the guide wire cavity, and the other end is a free end; in the initial state, the other end of the annular wall extends obliquely toward the distal end of the bendable section, so that the annular wall forms a tapered structure with a small inner diameter at the distal end and a large inner diameter at the proximal end, and the minimum inner diameter of the annular wall is greater than the diameter of the medical guide wire; in the limited state, the free end of the annular wall is bent and deformed toward the proximal end of the bendable section after being subjected to the force of the retraction of the medical guide wire, thereby making the inner diameter of the annular wall smaller than the diameter of the medical guide wire;

[0033] Alternatively, the retraction limiting portion is composed of a barb, one end of the barb is connected to the guidewire cavity, and the other end is a free end; in an initial state, the other end of the barb extends obliquely toward the distal end of the bendable section, and the distance from the end of the barb connected to the guidewire cavity to the inner wall of the guidewire cavity on the opposite side is greater than the outer diameter of the push rod, and the distance from the free end of the barb to the inner wall of the guidewire cavity on the opposite side is less than the outer diameter of the push rod; in a limited state, the free end of the barb is bent and deformed toward the proximal end of the bendable section after being subjected to the force of retraction of the medical guidewire, and then is stuck in the bayonet at the distal end of the push rod to limit the medical guidewire.

[0034] Optionally, the proximal end of the medical catheter is provided with a connecting valve, and the proximal end of the medical guide wire is provided with a fastening position; when the distal end of the medical guide wire enters the distal end of the medical catheter, the connecting valve is detachably connected to the proximal end of the medical guide wire at the fastening position.

[0035] Optionally, the medical system further includes a signal processing device communicatively connected to the medical guide wire, and the signal processing device is capable of amplifying and filtering the induction signal output by the induction coil.

[0036] The medical guidewire provided above includes: a distal portion and a push rod connected in sequence from far to near along its own axial direction; the push rod has an inner hole extending through it along its own axial direction; the distal portion includes at least one magnetic positioning sensor; the magnetic positioning sensor includes a magnetic core and an induction coil wound on the outer surface of the magnetic core; the induction coil leads to at least two wires, and at least two of the wires pass through the inner hole of the push rod and extend to the proximal end of the push rod.

[0037] This configuration imbues the medical guidewire with a three-dimensional magnetic positioning function, enabling visualization of the guidewire. Its movement and vibration can be monitored in real time during surgery to prevent vascular damage during exchange and increase surgical safety. When used in conjunction with a catheter during surgery, the guidewire can also be used to visualize tissue structure and the catheter, improving catheter passability, enhancing surgical safety, and reducing surgical complexity and intraoperative radiation dose.

[0038] It should be noted that since the medical system provided in this application and the medical guide wire provided in this application belong to the same inventive concept, the medical system provided in this application at least has all the beneficial effects of the medical guide wire provided in this application. For details, please refer to the relevant description of the beneficial effects of the medical guide wire provided in this application. Therefore, the beneficial effects of the medical system provided in this application will not be described one by one here. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Those skilled in the art will appreciate that the drawings are provided for a better understanding of the present application and do not constitute any limitation on the scope of the present application.

[0040] Figure 1 This is a schematic diagram of a medical guidewire passing through a medical catheter according to an embodiment of the present application.

[0041] Figure 2 This is a schematic diagram of an integral exchange type medical catheter according to an embodiment of the present application being pushed into a renal artery with the aid of a medical guide wire.

[0042] Figure 3 This is a schematic diagram of an integral exchange type medical catheter according to an embodiment of the present application positioned in place in the renal artery.

[0043] Figure 4 It is a schematic structural diagram of the medical guide wire of an embodiment of the present application.

[0044] Figure 5 This is a schematic diagram of the internal structure of the bendable section of the medical catheter and its guidewire cavity in an embodiment of the present application.

[0045] Figure 6 It is a structural schematic diagram of a medical guidewire according to another embodiment of the present application.

[0046] Figure 7 This is a structural schematic diagram of a medical guidewire according to another embodiment of the present application.

[0047] Figure 8 This is a schematic diagram of the internal structure of the bendable section of a medical catheter and its guidewire cavity according to another embodiment of the present application.

[0048] Figure 9 This is a schematic diagram of the glue coating on the distal end of the medical guide wire pushing rod in an embodiment of the present application.

[0049] In the attached figure:

[0050] 1-medical guidewire; 2-distal part; 3-push rod; 4-magnetic core; 5-induction coil; 6-conducting wire; 7-head cap; 8-sheath structure; 9-core structure; 91-reducing diameter section; 92-equal diameter section; 11-shaping structural part; 12-tapered transition section; 13-connecting tube; 14-first glue-coated section; 15-second glue-coated section; 20-medical catheter; 21-electrode section; 22-transition connection section; 23-bendable section; 24-catheter body; 25-handle; 26-guidewire cavity; 27-withdrawal limiter; 271-annular wall; 272-barb. DETAILED DESCRIPTION

[0051] To make the purposes, advantages, and features of this application more clear, the present application is further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale. They are only used to conveniently and clearly assist in illustrating the purposes of the embodiments of this application. In addition, the structures shown in the drawings are often part of the actual structure. In particular, different drawings may need to be presented with different emphases and may sometimes use different scales.

[0052] As used in this application, the singular forms "a," "an," "one," and "the" include plural referents, the term "or" is generally used to include "and / or," the term "several" is generally used to include "at least one," and the term "plurality" is generally used to include "two or more." Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly specifying the number of the technical features indicated. Thus, features defined as "first," "second," etc. may explicitly or implicitly include one or at least two of such features, and "one end" and "the other end" and "proximal end" and "distal end" generally refer to corresponding parts, not just endpoints. The terms "proximal end" and "distal end" are defined herein with respect to a medical catheter or medical guidewire having one end for insertion into the human body and a manipulation end extending outside the body. The term "proximal end" refers to the position closer to the control end of a medical catheter or medical guidewire that extends outside the body, and the term "distal end" refers to the position closer to the end of the medical catheter or medical guidewire that enters the human body and is therefore further away from the control end of the medical catheter or medical guidewire. Optionally, in manual or hand-operated applications, the terms "proximal end" and "distal end" are defined herein relative to an operator, such as a surgeon or clinician. The term "proximal end" refers to the position closer to the operator, and the term "distal end" refers to the position closer to the patient's affected area and is therefore further away from the operator. In addition, as used in this application, "mounted," "connected," "connected," and "disposed" of one element to another should be understood broadly and generally only indicate that there is a connection, coupling, mating, or transmission relationship between the two elements, and the connection, coupling, mating, or transmission between the two elements can be direct or indirect through an intermediate element, and should not be understood to indicate or imply a spatial positional relationship between the two elements, that is, one element can be in any orientation, such as inside, outside, above, below, or to the side of another element, unless the content clearly indicates otherwise. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances. In addition, directional terms such as above, below, up, down, upward, downward, left, right, etc. are used with respect to the exemplary embodiments as they are shown in the figures, with the upward or upper direction being toward the top of the corresponding figure and the downward or lower direction being toward the bottom of the corresponding figure. As used in this application, the term "axial" refers to the direction along the central axis of the entire medical device or corresponding structural component, the term "circumferential" refers to the direction around the central axis, and the term "radial" refers to the direction perpendicular to the axial direction, such as the diameter direction.

[0053] The purpose of the present application is to provide a medical guidewire and a medical system, which includes a medical guidewire and a medical catheter for use together. The medical catheter has a guidewire passage arranged along its own axis. When in use, the medical guidewire can be movably passed through the guidewire passage. Through the guidance of the medical guidewire, the medical catheter can be easily positioned in the blood vessel, especially the special-shaped tissue structure, thereby reducing the difficulty of surgical manipulation.

[0054] In particular, the medical guidewire described herein features a three-dimensional magnetic positioning function, enabling visualization of the guidewire. This allows real-time monitoring of the guidewire's movement and vibration during surgery, preventing damage to blood vessels during exchange and increasing surgical safety. Furthermore, the guidewire allows visualization of vascular tissue structure and catheters during surgery, improving catheter passability, enhancing surgical safety, and reducing surgical complexity and intraoperative radiation dose. This is described below with reference to the accompanying drawings.

[0055] First, refer to Figures 1 to 3 The present embodiment provides a medical system comprising a medical guidewire 1 and a medical catheter 20. The medical guidewire 1 is used in conjunction with the medical catheter 20. The medical catheter 20 can be any medical device capable of being passed through by the medical guidewire 1, such as an electrode catheter, or a non-electrode catheter such as a balloon catheter or an ultrasonic catheter. The specific structure and type of the medical catheter 20 are not limited. For ease of understanding, the following description uses an electrode catheter as an example.

[0056] Specifically, please refer to Figure 1 The electrode catheter may include an electrode segment 21, a transition connection segment 22, a bendable segment 23, a catheter body 24 and a handle 25 that are sequentially connected from far to near.

[0057] The electrode segment 21 has at least one electrode, preferably including at least the most distal head electrode. The electrode is used for mapping or ablation. In addition, when the electrode segment 21 includes multiple electrodes, the electrodes are connected by an insulating member and electrically isolated. It should be understood that a single electrode can perform monopolar stimulation and ablation, and multiple electrodes can perform bipolar stimulation and ablation in addition to monopolar stimulation and ablation, that is, inter-electrode stimulation and ablation, and can also perform multi-electrode simultaneous ablation. The material of the electrode can be a metal material that can be developed and conductive, such as platinum-iridium alloy, or a conductive material such as stainless steel and gold. The specific structure of the electrode segment 21 can be adjusted and changed according to the function of the catheter. For example, a number of holes can be provided inside the electrode segment 21 to allow for the placement of a saline tube, and accessories such as wires, temperature measurement and positioning sensors can also be installed. The electrode segment 21 can have different shapes, such as linear, annular, claw-shaped, flower-shaped, and other shapes that can be put in place for operation.

[0058] The transition section 22 connects the electrode section 21 and the flexible section 23. The transition section 22 is typically a single-lumen tube, while the flexible section 23 is a multi-lumen tube. The flexible section 23 is controlled by a pull wire, enabling bending control of the medical catheter 20, particularly bidirectional bending control, effectively improving the conformability of the medical catheter 20.

[0059] There are at least two pull wires, and at least two pull wires are symmetrically distributed in the medical catheter 20. Generally, all pull wires are arranged starting from the distal end of the bendable section 23, and then pass through the catheter body 24 and extend to the handle 25, and realize bending control under the control of the handle 25. The pull wires are mostly round wire structures. In some cases, the distal end of the pull wire can be welded with a flat wire, and the proximal end of the flat wire is terminated in the bendable section 23. The wider side of the flat wire is parallel to each other, thereby improving the symmetry of the bending control direction on both sides. Then, starting from the bending section 23, the two pull wires and the corresponding flat wires are respectively arranged in two symmetrical wire cavities. In this way, the two pull wires can realize functions such as bidirectional bending, positioning and abutment, and the installation direction of the flat wire can be adjusted to flexibly control the bending direction on both sides, such as 180° symmetrical bending on both sides or 90° vertical distribution.

[0060] In some cases, the bendable section 23 is a four-lumen tube containing four chambers; two symmetrical chambers are used as wire pulling chambers to achieve bidirectional bending control; the other two chambers are installed with polymer tubes, which are used for passing saline solution and medical guide wire 1 respectively; various wires are distributed along the gap between the inner wall of the four chambers and the outer wall of the polymer tube.

[0061] Specifically, the catheter body 24 is an elongated tube that interfaces with the multi-lumen tubing of the flexible section 23 and the handle 25. Typically, the catheter body 24 includes a braided layer, which strengthens the proximal end of the catheter, enhances its support, prevents deformation, and provides for proportional torque transmission.

[0062] In addition, the handle 25 can provide multiple functions, such as a wire bending control function, a saline infusion port, a guidewire inlet, an electrical stimulation energy interface, and a radiofrequency energy interface. Specifically, the handle 25 needs to be configured according to the function of the electrode catheter itself. For an electrode catheter, the proximal end of the handle 25 is often provided with an electrical stimulation energy-radiofrequency energy interface to achieve electrical stimulation and radiofrequency energy ablation. The proximal end of the handle 25 can also be provided with a guidewire inlet and a saline infusion port. The medical guidewire 1 and the infusion saline can be connected to the electrode catheter through the corresponding ports. In addition, a wire pulling system is provided inside the handle 25 to control the wire pulling system.

[0063] It should also be understood that the electrode catheter is provided with a guidewire path along its own axis, which extends from the electrode segment 21, the transition segment 22, the bendable segment 23, the catheter body 24, all the way to the handle 25, so that the guidewire can be placed in place in the blood vessel.

[0064] Continue to refer Figures 1 to 3 Taking the fully interchangeable medical catheter 20 as an example, the coordinated use of the medical guidewire 1 and the medical catheter 20 will be further described. According to the application scenario depicted in the figure, the medical catheter 20 is a fully interchangeable design that can be used with the medical guidewire 1 to be pushed, positioned, and withdrawn within the renal artery.

[0065] Taking transcatheter renal sympathetic denervation as an example, the surgical procedure is generally as follows: after completing transfemoral artery puncture and angiography, a medical catheter 20 is placed. The specific operation process is as follows:

[0066] First, if Figure 1 As shown, the medical guide wire 1 is fed into the medical catheter 20 along the guide wire passage of the medical catheter 20 in vitro, but the distal end of the medical guide wire 1 does not leak out of the distal end of the guide wire passage;

[0067] Then, if Figure 2 As shown, the medical catheter 20 is inserted into the sheath, and then the medical guide wire 1 is pushed to the distal end of the renal artery;

[0068] Then, if Figure 3 As shown, the medical catheter 20 is passed along the medical guide wire 1 across the renal artery orifice and the tortuous part of the blood vessel and enters the renal artery. After reaching the target position, the medical guide wire 1 is withdrawn, and the handle 25 is used to control the bend by pulling the wire to bend the flexible section 23, so that the distal end of the catheter is in contact with the blood vessel wall, and then stimulation and ablation are performed.

[0069] Thus, in actual use, the medical catheter 20 is pushed along the medical guidewire 1, making it easier to cross the renal artery ostium and tortuous areas, reach the target location, and achieve rapid contact through bidirectional bending control. It should also be understood that if the medical catheter 20 needs to be removed, it is only necessary to withdraw the medical catheter 20 in the body without withdrawing the medical guidewire 1, and then insert the medical catheter 20 to be used into the body along the medical guidewire 1. This can reduce damage to the blood vessels during the process of catheter switching using the guidewire.

[0070] Then, refer to Figure 4 The embodiment of the present application provides a medical guide wire 1, which includes: a distal portion 2 and a push rod 3 connected in sequence from far to near along its own axial direction; the push rod 3 has an inner hole extending through along its own axial direction; the distal portion 2 includes at least one magnetic positioning sensor; the magnetic positioning sensor includes a magnetic core 4 and an induction coil 5 wound on the outer surface of the magnetic core 4; the induction coil 5 leads to at least two wires 6, and the at least two wires 6 pass through the inner hole of the push rod 3 and extend to the proximal end of the push rod 3.

[0071] With this configuration, the distal end 2 of the medical guidewire 1 incorporates a built-in magnetic positioning sensor, which provides the guidewire 1 with a three-dimensional magnetic positioning function. This allows visualization of the guidewire 1. Furthermore, when the guidewire 1 is used in conjunction with the medical catheter 20 during surgery, not only can the three-dimensional structure of vascular tissue be intuitively displayed, but the curved shape of the catheter 20 during use can also be displayed in real time, presenting the catheter 20 to medical staff in a visual manner. This not only improves catheter passability and allows for more flexible placement, but also reduces surgical difficulty and intraoperative radiation dose, thereby increasing surgical safety and efficiency.

[0072] Optionally, the medical guidewire 1 has a specification of 0.014 inch to 0.038 inch. The most commonly used guidewire specifications are 0.014 inch, 0.035 inch, and 0.038 inch, which can accommodate the most commonly used medical catheters 20. Here, the guidewire specification refers to the guidewire diameter. In this embodiment, the guidewire diameter is the outer diameter of the push rod 3.

[0073] It should be understood that the material, shape and size of the magnetic core 4 can be adjusted and changed as needed. The magnetic core 4 can have a variety of shapes. Optionally, the shape of the magnetic core 4 is cylindrical, square, annular or other shapes. Preferably, the magnetic core 4 is cylindrical. There is no special restriction on the material of the magnetic core 4. Commonly used magnetic core materials include amorphous materials, ferrites, Permalloy, etc. In view of the applicable frequency band and initial magnetic permeability, it is preferred that the magnetic core 4 adopts an amorphous material with high magnetic permeability, little temperature influence and low eddy current loss. The magnetic core 4 can be a solid structure or a hollow structure, more preferably a solid structure.

[0074] When installing the magnetic core 4, at least two copper wires with insulating sheaths can be wound on the outer surface of the magnetic core 4 to form an induction coil 5. The induction coil 5 preferably has at least two wires 6 extending from its proximal end for signal transmission. In some cases, the induction coil 5 can have at least two wires 6 extending from the proximal end of the magnetic core 4.

[0075] After the induction coil 5 leads to at least two wires 6, the two wires 6 can take a variety of structural forms, such as a coaxial cable structure, a parallel cable structure or a twisted pair structure. Preferably, any induction coil 5 leads to two wires 6, and the two wires 6 form a twisted pair structure, that is, Figure 4 As shown in the figure, when a cable transmits data, current flows through the cores, generating some electromagnetic signals, which are harmful "noise" to other cores. Twisted-pair cables exist in pairs, and the "noise" emitted by the twisted wires 6 cancels each other out, thereby increasing transmission efficiency. In addition, compared to coaxial cables, twisted-pair cables have a smaller outer diameter and are more capable of withstanding tangles, pressure, and bending.

[0076] The wire 6 leading from the induction coil 5 is ultimately connected to the proximal end of the push rod 3. A socket can be provided at the proximal end of the push rod 3, and the wire 6 is connected to the socket by welding or other means. Specifically, the proximal end of the wire 6 is connected to the corresponding pin of the socket, enabling the transmission of the induction signal to the three-dimensional magnetic positioning device. Preferably, the socket can filter the induction signal output by the induction coil 5 to reduce signal interference and improve magnetic positioning accuracy.

[0077] In order to obtain high-quality magnetic positioning induction signals, the medical system preferably also includes a signal processing device that is communicatively connected to the medical guide wire 1. The signal processing device can amplify and filter the induction signal output by the induction coil 5 to obtain a more accurate induction signal and increase the magnetic positioning accuracy.

[0078] Further preferably, the distal part 2 may include a head cap 7, a sheath structure 8 and an internal structure; the head cap 7 is fixed to the distal end of the sheath structure 8; the sheath structure 8 is sleeved on the outside of the internal structure; the proximal end of the sheath structure 8 is connected to the distal end of the push rod 3, which can be directly or indirectly connected; the internal structure includes a core structure 9, the proximal end of the core structure 9 is connected to the distal end of the push rod 3, and at least part of the structure of the core structure 9 forms a magnetic core 4 and is wound with an induction coil 5, and the induction coil 5 preferably has at least two wires 6 led out from its proximal end.

[0079] The entire outer surface of the head cap 7 is smooth and flat, which can better protect the blood vessels. The main function of the head cap 7 is to increase the softness of the distal end of the guide wire, provide support, enhance tactile feedback, improve tracking, reduce friction, protect blood vessels, etc. For example, in some cases, the head cap 7 can also be developed under X-rays to increase visibility. Optionally, the head cap 7 is a developable structure, which is made of a suitable developable metal material, such as platinum iridium. Optionally, the head cap 7 is a gel ball formed by gel production or a molten ball formed by melting. The gel ball is soft and less likely to damage tissue structures such as blood vessels.

[0080] The outer diameter of the sheath structure 8 is typically less than or equal to the outer diameter of the push rod 3. The proximal end of the sheath structure 8 can be connected to the distal end of the push rod 3 or to the proximal end of the core structure 9. Furthermore, a gap is reserved between the inner side of the sheath structure 8 and the outer side of the core structure 9 to facilitate the installation of the induction coil 5. The radial dimensions of the induction coil 5 are primarily determined by the specifications of the medical guidewire 1. If the gap between the inner side of the sheath structure 8 and the outer side of the core structure 9 is sufficiently large, more layers and turns of the induction coil 5 can be installed, thereby increasing the accuracy of magnetic positioning.

[0081] The sheath structure 8 can have various structural forms, such as a spring coil, or a non-spring coil structure such as a plastic sheath structure, a polymer sheath structure, etc., which is not limited in this application. Preferably, the sheath structure 8 can be developed under X-rays. Specifically in this embodiment, the sheath structure 8 is a spring coil, and the spring coil as a whole can be developed. The wire material for winding the spring coil can be made of platinum alloy or other developable metal materials. The sheath structure 8 increases the flexibility of the distal end of the guide wire. In particular, when the sheath structure 8 can be developed, it also increases the visibility of the distal end of the guide wire, making it easier for the guide wire and catheter to pass through the tortuous structure. The outer surface of the sheath structure 8 may also have a coating, such as a hydrophilic coating or a hydrophobic coating. Preferably, the base of the sheath structure 8 is provided with a hydrophilic or hydrophobic coating after processing, and then applied to the medical guide wire 1.

[0082] Furthermore, the internal structure primarily serves as a magnetic positioning sensor, which is entirely encased within the sheath structure 8 and is not exposed. Consequently, the entire magnetic positioning sensor is relatively small, does not increase the overall diameter of the guidewire, and is less difficult to install than a magnetic positioning sensor at the distal end of the catheter. In practice, one or more magnetic positioning sensors can be installed between the distal end of the push rod 3 and the head cap 7.

[0083] It should be understood that such magnetic positioning sensors can be configured in many commonly used guidewires, making the medical guidewire 1 more flexible and safer in clinical applications, and can monitor the positioning of the guidewire and catheter in real time, and can cope with various complex vascular structures and lesions.

[0084] Preferably, the distal portion 2 also includes a shaping structure 11, which is located inside the sheath structure 8 and respectively connects the proximal end of the head cap 7 and the distal end of the core structure 9. The shaping structure 11 is a slender structure with a certain toughness and softness, and is usually made of metal. The provision of the shaping structure 11, on the one hand, increases the softness of the distal end of the guide wire and reduces damage to the tissue. On the other hand, during surgery, medical staff can shape the distal end of the guide wire according to the location and morphology of the lesion to adapt to the anatomical structure. The outer diameter of the shaping structure 11 is smaller than the outer diameter of the magnetic core 4. Optionally, the shaping structure 11 is composed of a filament.

[0085] Next, in the actual manufacturing process, one or more magnetic cores 4 can be manufactured through the core structure 9 .

[0086] Please refer to Figure 4In some embodiments, part of the core structure 9 forms a magnetic core 4. In this case, the core structure 9 includes a magnetic core 4, a variable diameter section 91, and a constant diameter section 92, which are connected in sequence from far to near along its own axial direction; the proximal end of the constant diameter section 92 is connected to the distal end of the push rod 3; the variable diameter section 91 and the constant diameter section 92 both have inner holes extending through along their own axial direction; the inner hole of the variable diameter section 91, the inner hole of the constant diameter section 92, and the inner hole of the push rod 3 are connected in sequence. In this embodiment, there is only one magnetic core 4, and a portion of the length of the magnetic core 4 is embedded in the inner hole of the variable diameter section 91 from the distal end of the variable diameter section 91 and fixed. The outer diameter of the variable diameter section 91 gradually increases from far to near along its entire length, which is a gradual design; the maximum outer diameter of the variable diameter section 91 is the same as the outer diameter of the constant diameter section 92, and the outer diameter of the constant diameter section 92 is smaller than the outer diameter of the push rod 3. Here, the advantage of providing the variable diameter section 91 is that the distal end of the guidewire has good support, torque conductivity, and pushing performance. In addition, the induction coil 5 wound on the magnetic core 4 leads out at least two wires 6 at the proximal end. These wires 6 can directly enter the inner hole of the reducing section 91 from the distal end of the reducing section 91 at the proximal end of the magnetic core 4, and then extend along the inner hole of the reducing section 91, the inner hole of the constant diameter section 92 and the inner hole of the push rod 3 to the proximal end of the push rod 3.

[0087] It is understood that the remaining portion of the core structure 9 (including the variable diameter section 91 and the constant diameter section 92) other than the magnetic core 4 is a non-magnetic structure. In this case, the magnetic core 4 and the remaining portion of the core structure 9 can be formed separately and then assembled. Specifically, a portion of the length of the magnetic core 4 is embedded in the inner hole of the variable diameter section 91 and fixed. The fixing method can be a combination of one or more fixing methods such as gluing, welding, etc. It should be understood that in other embodiments, the remaining portion of the core structure 9 can be entirely constant diameter sections 92, such as one or more constant diameter sections 92 of different diameters.

[0088] Preferably, a tapered transition section 12 is provided between the proximal end of the core structure 9 and the distal end of the push rod 3. For example, in this embodiment, the tapered transition section 12 is provided between the proximal end of the constant diameter section 92 and the distal end of the push rod 3. Throughout its entire length, the outer diameter of the tapered transition section 12 gradually increases from distal to proximal, reaching the outer diameter of the push rod 3. The tapered transition section 12 may have a linear or nonlinear taper. Optionally, the length of the tapered transition section 12 is 2 mm to 4 mm.

[0089] The remaining portion of the core structure 9, excluding the magnetic core 4, can be integrally formed or assembled from multiple sections. For example, the constant diameter section 92 and the variable diameter section 91 can be integrally formed, or they can be formed separately and then assembled together by welding or other suitable means. Similarly, the remaining portion of the core structure 9 and the push rod 3 can be integrally formed, or they can be formed separately and then assembled together, optionally by welding or other suitable means.

[0090] Optionally, the entire outer surface of the push rod 3 is provided with a hydrophilic coating or a hydrophobic coating to achieve good controllability. Preferably, the entire outer surface of the push rod 3 is provided with a PTFE hydrophobic coating. The push rod 3 is generally a slender rod that must meet certain mechanical performance requirements. The push rod 3 and the remaining portion of the core structure 9, excluding the magnetic core 4, can be made of various commonly used medical metal materials such as nickel-titanium alloy or stainless steel.

[0091] exist Figure 6 In a variation, the entire core structure 9 is configured as a single magnetic core 4 and a single induction coil 5. Compared to the previous embodiment, the length of the magnetic core 4 in this embodiment is equal to the length of the entire core structure 9, thereby increasing both the core length and the induction coil length. Preferably, the outer diameter of the core structure 9 remains constant throughout its entire length, from distal to proximal.

[0092] As another variation, part or all of the core structure 9 can form multiple magnetic cores 4, and the multiple magnetic cores 4 are distributed in sequence in the axial direction of the core structure 9, for example, continuously or discretely or both. An induction coil 5 is wound on the outer surface of each magnetic core 4, and each induction coil 5 is independent of each other. Each induction coil 5 leads to at least two wires 6, and all wires 6 converge at the proximal end of the core structure 9 and then pass through the same inner hole of the push rod 3 to extend to the proximal end of the push rod 3. In this embodiment, each magnetic core 4 is functionally independent, and an induction coil 5 is wound on the outer surface of each magnetic core 4. Each induction coil 5 is also independent of each other and not connected. In this way, it is equivalent to providing multiple independent magnetic positioning sensors in the distal part 2 of the medical guide wire 1, and each magnetic positioning sensor includes an induction coil 5 and a corresponding magnetic core 4. Such a setting allows the same medical guide wire 1 to accommodate multiple high-sensitivity magnetic positioning sensors at the distal end, making the magnetic positioning more accurate and reliable.

[0093] Here, with Figure 7 The exemplary embodiments described in the following are used for illustration. Figure 7As shown, part of the structure of the core structure 9 forms, for example, three independent magnetic cores 4, and adjacent magnetic cores 4 are connected by connecting tubes 13. A wire 6 can be passed through the interior of the connecting tube 13, or the wire 6 can be directly arranged on the outside of the connecting tube 13. In this embodiment, each connecting tube 13 can also be passed through a wire 6 (preferably a twisted pair), so that the wire 6 of the induction coil 5 on some magnetic cores 4 can be routed between adjacent magnetic cores 4 through the connecting tube 13. In some cases, the wire 6 can also be routed through the inner hole of some magnetic cores 4. In this embodiment, the wire 6 is arranged along the outside of the magnetic core 4 after coming out of the connecting tube 13. The connecting tube 13 can be sleeved on one end of the magnetic core 4 or one end of the magnetic core 4 can be embedded in the connecting tube 13, and then fixed, and the fixing method is welding or gluing, etc. Preferably, the magnetic core 4 and the connecting tube 13 are fixed by pouring glue into the connecting tube 13. It should be understood that multiple magnetic cores 4 can also be connected as a whole through a connecting tube 13, and this application is not limited to this.

[0094] The magnetic positioning design of the medical guide wire 1 is further explained below.

[0095] Since the self-made magnetic positioning sensor needs to be installed at the distal end of the guidewire in a narrow space, the voltage sensitivity of the induction coil 5 should be μ higher than that of the hollow induction coil. c times. c The calculation formula is as follows:

[0096]

[0097] In formula (1): N d is the demagnetization coefficient, which is determined by the shape of the core 4; for example, for an oblong, μ r is the initial magnetic permeability of the magnetic core 4; l is the length of the magnetic core 4; d is the diameter (ie, outer diameter) of the magnetic core 4; ln is the logarithm, and ln2l is the logarithm of 2l.

[0098] According to formula (1), μ can be calculated c , according to the calculated μ c It is then known whether the voltage sensitivity of the induction coil 5 meets the product requirements. Conversely, the shape and size of the magnetic core 4 can be optimized based on the voltage sensitivity, and ultimately the appropriate shape and size of the magnetic core 4 can be selected to achieve the best magnetic positioning effect.

[0099] It should be understood that magnetic permeability is a material property. Therefore, given a given material, the shape and dimensions (including diameter and length) of the core 4 are crucial to magnetic induction design. Therefore, during actual development, adjusting the shape and dimensions of the core 4 can satisfy requirements for magnetic positioning accuracy, sensitivity, and signal strength. As previously mentioned, the reduction in magnetic positioning accuracy caused by noise introduced by the core 4 can be addressed through circuit compensation, such as filtering and amplification.

[0100] Optionally, the outer diameter of the magnetic core 4 is 0.15mm-0.18mm, such as 0.15mm, 0.16mm, 0.17mm, 0.18mm, etc., and the length of the magnetic core 4 is 4mm-4.4mm, such as 4.0mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, etc.; this size is particularly suitable for a medical guide wire 1 with a specification of 0.014inch, for example, the outer diameter of the distal portion 2 is 0.26mm-0.33mm, such as 0.26mm, 0.27mm, 0.28mm, 0.29mm, 0.30mm, 0.31mm, 0.32mm, 0.33mm, etc., and the inner diameter of the sheath structure 8 is not less than (i.e., greater than or equal to) 0.2mm.

[0101] In addition, considering that the magnetic induction intensity of the magnetic core 4 is the largest at the center and the sensitivity is the highest, it is preferable that the length of the induction coil 5 accounts for 75%-90% of the length of the magnetic core 4, such as 75%, 80%, 85% or 90%. For example, in this embodiment, the length of the magnetic core 4 embedded in the diameter-reducing section 91 accounts for 10%-25% of the length of the magnetic core 4, such as 10%, 15%, 20% or 25%, ensuring that the magnetic core 4 is firmly fixed while taking into account sensitivity. In a specific example, when the specification of the medical guide wire 1 is 0.014 inches, the length of the magnetic core 4 is 4 mm. In order to avoid edge effects, the induction coil 5 can be wound within a length range of 3 mm to 3.5 mm in the center of the magnetic core 4, that is, the length of the induction coil 5 accounts for 75%-90% of the length of the magnetic core 4, such as 75%, 80%, 85%, 90%, ensuring the sensitivity of magnetic positioning.

[0102] While ensuring that the magnetic field changes significantly and does not burn the copper wire of the coil, the wire diameter of the induction coil 5 is preferably 20μm-30μm, such as 20μm, 25μm or 30μm. In addition, the number of winding layers and the number of winding turns of the induction coil 5 can be adjusted according to the coil wire diameter, the inner diameter of the sheath structure 8 and the outer diameter of the magnetic core 4. Optionally, the number of winding layers of the induction coil 5 does not exceed 2 layers, and the number of winding turns of the induction coil 5 does not exceed 280 turns. In this case, preferably, the wire diameter is 20μm-30μm, such as 20μm, 25μm, and 30μm, and the gap between the inner side of the sheath structure 8 and the outer side of the magnetic core 4 is 20μm-50μm, such as 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, and 50μm.

[0103] Preferably, the outer surface of the magnetic core 4 is provided with a pattern that can accommodate the wire 6 wound around the induction coil 5, thereby defining the position of the induction coil 5 and ensuring magnetic positioning accuracy and sensitivity. The shape and size of the pattern are set according to the winding shape and size of the wire 6. Optionally, the diameter of the pattern is consistent with the wire diameter of the wire 6, the depth of the pattern is equal to the radius of the wire 6, and the spacing between the patterns is the spacing between the windings. Optionally, the pattern spacing accuracy reaches 1μm, which can ensure the winding accuracy of the induction coil 5 during assembly.

[0104] It should be understood that another key to magnetic induction design is the inductance value. For example, the ratio of the length of the induction coil 5 to the length of the magnetic core 4 is When the value of β is 0.1-0.8, the inductance calculation formula is:

[0105]

[0106] In formula (2): L is the inductance; μ0 is the vacuum permeability; μ c is the relative magnetic permeability of the core; A c is the cross-sectional area of ​​the coil; l is the length of the core; N is the total number of turns of the coil; b w is the coil length.

[0107] According to formula (2), the inductance value of the induction coil 5 can be calculated to obtain the sensitivity. Conversely, based on the inductance value, the shape and size of the induction coil 5 can be further optimized, and finally the appropriate shape and size of the induction coil 5 can be selected to achieve the best magnetic positioning effect.

[0108] Further research found that when the medical guidewire 1 is retracted, if the push rod 3 of the medical guidewire 1 is in the bendable section 23 of the medical catheter 20, the adjustable bending deformation ability of the medical catheter 20 will be weakened, the bending control force will be increased, and the difficulty of bending control will be increased.

[0109] For this reason, on the one hand, Figure 4As shown, a rubber coating layer is provided at the connection between the proximal end of the core structure 9 and the distal end of the push rod 3. Specifically, the rubber coating layer is provided on the outer surface of the tapered transition section 12, and the outer diameter of the rubber coating layer is less than or equal to the outer diameter of the push rod 3. The rubber coating layer is of a gradual design, with the outer diameter gradually increasing from far to near, and the maximum outer diameter is less than or equal to the outer diameter of the push rod 3. In a specific example, the maximum outer diameter of the rubber coating layer is less than or equal to 0.014 inches. The rubber coating layer is formed by coating with glue and has a certain viscosity. When the medical guide wire 1 is retracted, it can increase the withdrawal resistance at the connection between the proximal end of the core structure 9 and the distal end of the push rod 3, so as to limit the medical guide wire 1.

[0110] On the other hand, Figure 5 As shown, the medical catheter 20 includes a bendable section 23, and the guidewire passage includes a guidewire lumen 26 disposed within the bendable section 23. A retraction limiter 27 is disposed at the proximal end of the guidewire lumen 26. The retraction limiter 27 has an initial state and a limited state, and can switch between the initial state and the limited state.

[0111] In the initial state, the retraction limit portion 27 can allow the medical guide wire 1 to pass normally without increasing the pushing resistance. That is, when the medical guide wire 1 is pushed from the proximal end to the distal end in the guide wire passage, the distal part 2 of the medical guide wire 1 and the pushing rod 3 can both pass through the retraction limit portion 27 smoothly.

[0112] In the limited state, the withdrawal limit portion 27 is deformed by the force of the withdrawal of the medical guide wire 1, thereby preventing the connection between the distal part 2 of the medical guide wire 1 and the push rod 3 from passing through, so that the connection between the distal part 2 and the push rod 3 is limited to the withdrawal limit portion 27, thereby preventing the push rod 3 from staying in the flexible section 23 and affecting the bending control of the medical catheter 20.

[0113] Specifically in this embodiment, in the limited state, the retraction limit portion 27 prevents the connection between the proximal end of the core structure 9 and the distal end of the push rod 3 from passing through, so that the connection between the proximal end of the core structure 9 and the distal end of the push rod 3 is limited to the retraction limit portion 27, especially after a rubber layer is provided at the connection, the rubber layer increases the resistance of the connection during retraction, making the connection easily blocked by the retraction limit portion 27.

[0114] The withdrawal limit portion 27 is made of a polymer material with good toughness and is relatively soft. The withdrawal limit portion 27 can achieve the above-mentioned functions through a variety of measures. Although this embodiment is described in conjunction with the annular wall 271 in the accompanying drawings, it should be understood that a variety of other limiting methods can also be used. Although the annular wall 271 of this embodiment may have a simpler structure, be more convenient to use, and have less impact on the performance of the bendable section 23, this embodiment should not be limited to this structural method. Therefore, in addition to the structure of the withdrawal limit portion 27 listed in the accompanying drawings, technical personnel in the relevant field can find other alternative methods based on the records of this application specification to achieve the functions recorded in this application / achieve the above-mentioned effects, not just the solutions disclosed in this embodiment.

[0115] Preferably, Figure 5 As described in the specification, the withdrawal limit portion 27 is an annular wall 271, one end of which is connected to the inner wall of the guidewire cavity 26, and the other end is a free end. In the initial state (naturally open), the other end of the annular wall 271 extends obliquely toward the distal end of the bendable segment 23, so that the annular wall 271 forms a tapered structure with a small distal inner diameter (D2) and a large proximal inner diameter (D1). However, the minimum inner diameter (D2) of the annular wall 271 is still larger than the diameter of the medical guidewire 1, so that the distal portion 2 and the push rod 3 can pass normally. Furthermore, in the limited state, the free end of the annular wall 271 is bent and deformed toward the proximal end of the bendable segment 23 after being subjected to the force of the medical guidewire 1 withdrawing, so that the inner diameter (D3) of the annular wall 271 is smaller than the diameter of the medical guidewire 1, thereby hindering the withdrawal of the medical guidewire 1, and ultimately limiting the connection between the proximal end of the core structure 9 and the distal end of the push rod 3 to the proximal end of the bendable segment 23.

[0116] The withdrawal limit portion 27 can be a continuous annular wall 271, or an annular wall 271 defined by a plurality of discrete barbs 272. Here, the continuous annular wall 271 refers to an entire annular wall as shown in the accompanying drawings, while the discrete annular wall 271 refers to a plurality of independent barbs 272, which are arranged along the circumference of the guidewire cavity 26. One end of each barb 272 is connected to the inner wall of the guidewire cavity 26, and the other end is a free end. When naturally opened, the other end of the barb 272 extends obliquely toward the distal end of the bendable section 23. In this embodiment, the retraction limit portion 27 is composed of a plurality of independent barbs 272; when viewed from the proximal end to the distal end, the setting direction of each barb 272 just conforms to the pushing direction of the medical guide wire 1 and does not hinder the pushing of the medical guide wire 1; when viewed from the distal end to the proximal end, the setting direction of each barb 272 just goes against the retraction direction of the medical guide wire 1. Therefore, the medical guide wire 1 can be limited to this position when retracting, without affecting the adjustable bend of the medical catheter 20, and the medical guide wire 1 will not move or vibrate at will.

[0117] For example, to ensure the passability of medical guidewire 1 during push and positioning during withdrawal, the thickness of barbs 272 is set to d, where D1 = D-2d > 0.014 inch, D2 = D-3d > 0.014 inch, and D3 = D-4d < 0.014 inch, where D is a fixed value and 0.014 inch is the diameter of medical guidewire 1. Based on this, when pushing medical guidewire 1, the pushing force is directed in the direction of barbs 272, allowing both distal end 2 and push rod 3 to pass through. When withdrawing, push rod 3 can normally retract through barbs 272, especially when the surface of push rod 3 is coated with a PTFE lubricant coating, which makes it easier for push rod 3 to retract through barbs 272. It should be understood that the surface of the glue coating (i.e., the rubber layer) at the connection between the core structure 9 and the push rod 3 is sticky, and the resistance during retraction is large, and the retraction force is opposite to the direction of the barb. The barb is easy to bend in the proximal direction, and the inner diameter D3 after bending can hinder the medical guide wire 1 from continuing to retract, thereby limiting the connection between the core structure 9 and the push rod 3 to the proximal end of the bendable section 23.

[0118] like Figure 8 and Figure 9 As shown, in another embodiment, the retraction limiter 27 consists of only one barb 272. Specifically, a barb 272 is provided on the inner wall of the guidewire lumen 26 near the outer side of the catheter at the proximal end of the bendable section 23. The barb 272 extends locally along the circumference of the inner wall of the guidewire lumen 26, rather than being arranged in a circle. The barb 272 occupies approximately 1 / 4 to 1 / 2 of the circumference of the inner wall of the guidewire lumen 26. In this embodiment, one end of the barb 272 is connected to the inner wall of the guidewire lumen 26, and the other end is free. When naturally opened, the other end of the barb 272 extends obliquely toward the distal end of the bendable section 23, and the distance D4 from the end of the barb 272 connected to the guidewire lumen 26 to the inner wall of the opposite guidewire lumen 26 is greater than the outer diameter of the push rod 3. When the barb 272 is naturally opened, the distance D5 from the free end of the barb 272 to the inner wall of the opposite guidewire lumen 26 is less than the outer diameter of the push rod 3.

[0119] At the same time, when applying glue circumferentially to the distal end of the push rod 3, a first glue-coating section 14 is provided on a portion of the outer surface of the tapered transition section 12 along the circumferential direction, and a second glue-coating section 15 is provided on the other portion. The outer diameter of the first glue-coating section 14 gradually decreases from distal to proximal, forming a V-shaped bayonet at the proximal end. The coating range of the first glue-coating section 14 along the circumferential direction of the outer surface of the tapered transition section 12 is substantially consistent with the circumferential extension range of the barbs 272 along the inner wall of the guidewire lumen, for example, occupying approximately 1 / 4 to 1 / 2 of the circumference of the outer surface of the tapered transition section 12. Therefore, the first glue-coating section 14 and the second glue-coating section 15 are arranged relative to each other on the outer surface of the tapered transition section 12, so that the first glue-coating section 14 is formed on a portion of the outer surface of the tapered transition section 12 along the circumference, and the remaining portion is the second glue-coating section 15. The second glue-coating section 15 has a constant outer diameter from distal to proximal, and its outer diameter is consistent with the outer diameter of the sheath structure 8. Based on this, when the medical guide wire 1 is retracted, the free end of the barb 272 will be subjected to the force of the retraction of the medical guide wire 1, and then bend and deform toward the proximal end of the bendable section 23, and then can be stuck in the bayonet at the distal end of the push rod 3 to limit the medical guide wire 1.

[0120] In addition, when the proximal end of the medical guidewire 1 is fastened, preferably, the positioning mark at the fastening position is set on the same side of the medical guidewire 1 as the first adhesive section 14. When withdrawing, the positioning mark can be kept on the same side as the barb 272 to serve as an indicator. Specifically, when the medical guidewire 1 is pushed from the proximal end to the distal end of the medical catheter 20, the positioning mark at the proximal end of the medical guidewire 1 is directed away from the outside of the medical catheter 20, that is, the first adhesive section 14 is located on the opposite side of the barb 272. Then, when passing through the guidewire lumen 26, the second adhesive section 15 can slide smoothly over the barb 272, ensuring that the medical guidewire 1 can pass normally. On the contrary, when the medical guide wire 1 is retracted, the positioning mark at the proximal end of the medical guide wire 1 is directed toward the outside of the medical catheter 20, so that the first glue-coated section 14 is located exactly on the same side of the barb 272, and then when passing through the guide wire cavity 26, the barb 272 in the guide wire cavity 26 can be stuck in the bayonet at the proximal end of the first glue-coated section 14, thereby limiting the medical guide wire 1.

[0121] On the other hand, when performing three-dimensional modeling, the position of the medical guide wire 1 in the blood vessel fluctuates greatly and cannot always maintain a close contact with the blood vessel wall, which will affect the accuracy of the modeling.

[0122] In a further improvement, the proximal end of the push rod 3 is provided with a fastening position. The distance from the fastening position to the distal end of the medical guidewire 1 is the same as the distance from the distal end of the medical catheter 20 to the proximal guidewire entrance. Thus, during surgery, the medical guidewire 1 can be detachably connected to the proximal end of the medical catheter 20 at the fastening position, thereby limiting the position of the medical guidewire 1 and preventing it from moving or vibrating at will. Furthermore, when the medical guidewire 1 is connected to the medical catheter 20 at the fastening position, the distal end 2 of the medical guidewire 1 is ensured to be precisely accommodated within the distal end of the medical catheter 20. This allows for high-precision three-dimensional modeling through the contact between the distal end of the medical catheter 20 and the blood vessel wall. It is understandable that during three-dimensional modeling, it is necessary to ensure that the magnetic positioning sensor at the distal end of the medical guidewire 1 is inside the distal end of the medical catheter 20. At this time, with the help of the distal end of the medical catheter 20 being in contact with the blood vessel wall, the magnetic positioning data of the distal end of the catheter is obtained. Then, during the magnetic positioning calculation, it is only necessary to increase the position compensation of the catheter radius size to achieve three-dimensional modeling of the catheter and vascular tissue.

[0123] Preferably, a positioning mark is provided at the fastening position, and the positioning mark can be provided in a variety of ways, such as optional laser marking, engraving, etching, etc. Such a setting enables medical staff to quickly determine the position of the medical guide wire 1 based on the positioning mark. When three-dimensional modeling is required, after determining the position of the medical guide wire 1, the proximal end of the medical guide wire 1 is connected to the medical catheter 20 at the fastening position to prevent the medical guide wire 1 from shifting, so as to achieve high-precision modeling. In view of the fact that there is a connecting valve at the proximal end of the medical catheter 20, such as a Y-shaped hemostatic valve or other connecting valve, when the distal part 2 of the medical guide wire 1 enters the distal end of the medical catheter 20, the proximal end of the medical guide wire 1 can be detachably connected through the connecting valve provided at the proximal end of the catheter to limit the position of the medical guide wire 1.

[0124] As a result, while the medical guidewire 1 is moving within a blood vessel, real-time 3D modeling of the vessel can be performed online and displayed, making the surgical procedure more intuitive and visual. Furthermore, during the procedure, the handle 25 of the medical catheter 20 can control the bendable section 23, enabling bidirectional deflection of the distal end of the catheter, thereby increasing the contact force and flexibility in controlling the bending direction. The 3D modeling method is well understood by those skilled in the art and will not be further described.

[0125] In summary, according to the technical solutions provided in the embodiments of the present application, a custom magnetic positioning sensor can be fabricated on a medical guidewire 1, providing the medical guidewire 1 with a three-dimensional magnetic positioning function, thereby enabling visualization of the medical guidewire 1. Furthermore, the movement and vibration of the medical guidewire 1 can be monitored in real time during surgery to prevent damage to blood vessels during exchange and increase surgical safety. In particular, when the medical guidewire 1 is used in conjunction with a medical catheter 20 during surgery, in addition to visually displaying the three-dimensional structure of vascular tissue, the catheter's curved state during use can also be displayed in real time, presenting the catheter in a visual state. This improves catheter passability, enhances surgical safety, and reduces surgical complexity and intraoperative radiation dose.

[0126] Finally, it should be noted that while the above description uses renal artery ablation as an example, it is not limited to this. The medical catheter 20 provided in this embodiment can also be used for ablation of various locations, such as cardiac ablation and bronchial ablation. Furthermore, the medical catheter 20 is not limited to an ablation catheter and can also be a variety of other medical catheters. In practice, as long as the medical catheter 20 can be inserted into a blood vessel with the medical guidewire 1, the medical guidewire 1 can be used to guide the medical catheter 20 to the target location, and the medical guidewire 1 can be used to visualize the vascular tissue structure, the guidewire, and the catheter.

[0127] It should be noted that the above embodiments can be combined with each other. The above description is only a description of the preferred embodiments of the present application and does not limit the scope of the present application. Any changes or modifications made by ordinary technicians in the field of the present application based on the above disclosure are within the scope of protection of the present application.

Claims

1. A medical guide wire, characterized in that: include: The distal part and the push rod are connected in sequence from far to near along its own axial direction; the push rod has an inner hole extending through along its own axial direction; the distal part includes at least one magnetic positioning sensor; the magnetic positioning sensor includes a magnetic core and an induction coil wound on the outer surface of the magnetic core; the induction coil leads to at least two wires, and at least two of the wires pass through the inner hole of the push rod and extend to the proximal end of the push rod.

2. The medical guide wire according to claim 1, characterized in that The distal part also includes a head cap, a sheath structure and an internal structure; the head cap is fixed to the distal end of the sheath structure; the sheath structure is sleeved on the outside of the internal structure; the internal structure includes a core structure, the proximal end of the core structure is connected to the distal end of the push rod, and at least part of the core structure forms a magnetic core and is wound with the induction coil, and the induction coil leads out at least two of the wires at its proximal end.

3. The medical guide wire according to claim 2, characterized in that Part of the structure of the core structure forms a magnetic core, and the core structure includes a magnetic core, a variable diameter section and a constant diameter section connected in sequence from far to near along its own axial direction; the proximal end of the constant diameter section is connected to the distal end of the push rod; the variable diameter section and the constant diameter section both have an inner hole extending through along their own axial direction; the inner hole of the variable diameter section, the inner hole of the constant diameter section and the inner hole of the push rod are connected in sequence; a part of the length of the magnetic core is embedded in the inner hole of the variable diameter section from the distal end of the variable diameter section and fixed; the outer diameter of the variable diameter section gradually increases from far to near throughout its entire length; the maximum outer diameter of the variable diameter section is the same as the outer diameter of the constant diameter section; the outer diameter of the constant diameter section is smaller than the outer diameter of the push rod; at least two of the wires extend from the distal end of the variable diameter section into the inner hole of the variable diameter section, and then extend along the inner hole of the variable diameter section, the inner hole of the constant diameter section and the inner hole of the push rod to the proximal end of the push rod.

4. The medical guide wire according to claim 2, characterized in that A tapered transition section is provided between the proximal end of the core structure and the distal end of the push rod, and the outer diameter of the tapered transition section gradually increases from distal to proximal throughout its entire length.

5. The medical guide wire according to claim 2, characterized in that The entire structure of the core structure forms one magnetic core; or, part or all of the structure of the core structure forms multiple magnetic cores, and the multiple magnetic cores are distributed in sequence in the axial direction of the core structure. An induction coil is wound on the outer surface of each magnetic core, and each induction coil is independent of each other. Each induction coil leads out at least two wires at its proximal end, and all the wires pass through the same inner hole of the push rod and extend to the proximal end of the push rod.

6. The medical guide wire according to claim 2, characterized in that The distal portion further comprises a shaping structure, which is located inside the sheath structure and respectively connects the proximal end of the head cap and the distal end of the core structure.

7. The medical guide wire according to claim 4, characterized in that A rubber coating layer is provided on the entire outer surface of the conical transition section, the outer diameter of the rubber coating layer gradually increases from far to near, and the maximum outer diameter of the rubber coating layer is less than or equal to the outer diameter of the push rod.

8. The medical guide wire according to claim 2, characterized in that The head end cap is a developable structure, or the head end cap is a gel ball formed by gel production or a molten ball formed by melting.

9. The medical guide wire according to claim 1 or 2, characterized in that: Two conductive wires are led out from any of the induction coils, and the two conductive wires form a twisted pair structure.

10. The medical guide wire according to claim 1 or 2, characterized in that: A socket is provided at the proximal end of the pushing rod, the induction coil is connected to the socket via at least two of the lead-out wires, and the socket can filter the induction signal output by the induction coil.

11. The medical guide wire according to claim 1 or 2, characterized in that: The proximal end of the push rod is provided with a fastening position, and the distance from the fastening position to the distal end of the medical guide wire is the same as the distance from the distal end of the medical catheter to the proximal guide wire entrance; the medical guide wire is used to be detachably connected to the proximal end of the medical catheter at the fastening position; When the medical guide wire is connected to the medical catheter at the fastening position, the distal end portion is accommodated inside the distal end of the medical catheter.

12. The medical guide wire according to claim 11, characterized in that A positioning mark is provided at the fastening position; a conical transition section is provided at the distal end of the push rod, a first glue-coated section is provided on a part of the outer surface of the conical transition section along the circumferential direction, and a second glue-coated section is provided on the other part, the outer diameter of the first glue-coated section gradually decreases from far to near, and a bayonet is formed at the proximal end, and the second glue-coated section has a constant outer diameter from far to near; the positioning mark is provided on the same side as the first glue-coated section.

13. The medical guide wire according to claim 1 or 2, characterized in that: The magnetic positioning sensor has at least one of the following features: The outer surface of the magnetic core is provided with textures to accommodate the wire wound around the induction coil; The length of the induction coil accounts for 75%-90% of the length of the magnetic core; The wire diameter of the induction coil is 20 μm-30 μm; The number of winding layers of the induction coil does not exceed 2 layers, and the number of winding turns of the induction coil does not exceed 280 turns; The outer diameter of the magnetic core is 0.15mm-0.18mm, and the length of the magnetic core is 4mm-4.4mm; The magnetic core is a solid structure or a hollow structure; The magnetic core is made of amorphous material.

14. The medical guide wire according to claim 1 or 2, characterized in that: The specification of the medical guide wire is 0.014 inch to 0.038 inch.

15. A medical system, characterized in that: include: A medical catheter and a medical guidewire according to any one of claims 1 to 14; the medical catheter having a guidewire passage extending axially therethrough; The medical guide wire is used to movably pass through the guide wire passage.

16. The medical system according to claim 15, characterized in that The medical catheter includes a bendable section, and the guidewire passage includes a guidewire cavity disposed within the bendable section; a retraction limiter is disposed at a proximal end of the guidewire cavity; the retraction limiter has an initial state and a limit state, and is capable of switching between the initial state and the limit state; In the initial state, the retraction limit portion can allow the distal end portion of the medical guide wire and the push rod to pass through; In the limited state, the retraction limit portion is deformed after being subjected to the retraction force of the medical guide wire, thereby preventing the connection between the distal end of the medical guide wire and the push rod from passing through, so that the connection between the distal end of the medical guide wire and the push rod is limited in the retraction limit portion, thereby preventing the push rod from staying in the bendable section.

17. The medical system according to claim 16, wherein: The retraction limiting portion is an annular wall, one end of which is connected to the guidewire cavity, and the other end is a free end; in the initial state, the other end of the annular wall extends obliquely toward the distal end of the bendable section, so that the annular wall forms a tapered structure with a small inner diameter at the distal end and a large inner diameter at the proximal end, and the minimum inner diameter of the annular wall is greater than the diameter of the medical guidewire; in the limited state, the free end of the annular wall is bent and deformed toward the proximal end of the bendable section after being subjected to the force of the retraction of the medical guidewire, thereby making the inner diameter of the annular wall smaller than the diameter of the medical guidewire; Alternatively, the retraction limit portion is composed of a barb, one end of which is connected to the guidewire cavity and the other end is a free end; In the initial state, the other end of the barb extends obliquely toward the distal end of the bendable section, and the distance from the end of the barb connected to the guidewire cavity to the inner wall of the guidewire cavity on the opposite side is greater than the outer diameter of the push rod, and the distance from the free end of the barb to the inner wall of the guidewire cavity on the opposite side is less than the outer diameter of the push rod; in the limited state, the free end of the barb is bent and deformed toward the proximal end of the bendable section after being subjected to the force of the retraction of the medical guidewire, and then is stuck in the bayonet at the distal end of the push rod to limit the medical guidewire.

18. The medical system according to claim 15, wherein: The proximal end of the medical catheter is provided with a connecting valve, and the proximal end of the medical guide wire is provided with a fastening position; when the distal end of the medical guide wire enters the distal end of the medical catheter, the connecting valve is detachably connected to the proximal end of the medical guide wire at the fastening position.

19. The medical system according to claim 15, wherein: It also includes a signal processing device that is communicatively connected to the medical guide wire, and the signal processing device can amplify and filter the induction signal output by the induction coil.

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