Adjustable bending microguide wire

Abstract

The application relates to the field of medical devices and discloses an adjustable bending micro guide wire, which comprises a guide wire mandrel, a nickel-titanium alloy hypotube and a local heating part, the nickel-titanium alloy hypotube is arranged outside the guide wire mandrel, the nickel-titanium alloy hypotube has a bending section at a distal end, and the bending section is a bending section formed by a double-path shape memory response through thermal mechanical cycle training; the guide wire mandrel, the nickel-titanium alloy hypotube bending section at the distal end of the guide wire and the local heating part arranged at the distal end corresponding to the bending section are arranged, the bending section is formed by a double-path shape memory response through thermal mechanical cycle training, the local heating part can locally heat the bending section and trigger the bending section to switch between a straight state and a preset bending state, the micro guide wire can complete distal end direction adjustment without relying on a mechanical traction wire penetrating through the whole length, and response lag, friction loss and proximal unintended deformation caused by long-distance traction transmission are reduced.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more particularly to adjustable bendable microguidewires. Background Technology

[0002] Microguidewires are commonly used guiding devices in neurointerventional, cardiovascular interventional, and peripheral vascular interventional surgeries. They are typically used to provide guidance and support for microcatheters, balloons, stents, or thrombectomy devices as they pass through blood vessels. In complex anatomical structures such as intracranial aneurysms, bifurcation lesions, and tortuous stenotic vessels, the directional control capability of the distal end of the microguidewire directly affects whether the device can successfully enter the target blood vessel or lesion area.

[0003] A search revealed that CN112891711B discloses a medical interventional guidewire with controllable steering, which achieves guidewire steering control through the combination of a shape memory alloy layer and temperature changes; US5904657A discloses a system for guiding intracavitary instruments, in which the guidewire is made of shape memory alloy and has a cavity, and an optical fiber is installed in the cavity. The optical fiber can selectively and locally heat the guidewire to change its shape.

[0004] Existing microguidewires rely on long-distance mechanical traction transmission, making it difficult to stably switch the distal bending segment between preset shapes by triggering local heating without relying on a long-distance mechanical traction structure. Summary of the Invention

[0005] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an adjustable-bend microguidewire, which solves the problem that existing microguidewires are unable to stably switch between preset shapes by triggering the distal bending segment through local heating without relying on a long-distance mechanical traction structure.

[0006] (II) Technical Solution To achieve the above objectives, the present invention is implemented through the following technical solutions.

[0007] An adjustable-bend microguidewire includes a guidewire mandrel, a nickel-titanium alloy thiosulfate tube, and a local heating element. The nickel-titanium alloy thiosulfate tube is disposed on the outside of the guidewire mandrel and has a curved section at its distal end. The curved section is a curved section that has formed a two-way shape memory response through thermomechanical cycle training. The curved section can present a straight state and a preset curved state under different temperature conditions. The distal end of the local heating element is disposed corresponding to the curved section and is used to locally heat the curved section to trigger the curved section to switch between the straight state and the preset curved state.

[0008] In one embodiment, the curved segment can be straight at a first temperature, curved in a first direction at a second temperature, and curved in a second direction at a third temperature, wherein the bending directions of the first and second curved directions are different.

[0009] Preferably, the first temperature state is 35℃-38℃, the second temperature state is 39℃-42℃, and the third temperature state is 45℃-52℃.

[0010] In one embodiment, the curved segment is straight at a first temperature, bends to the right at a second temperature, and bends to the left at a third temperature, with the bending angle of the right and / or left bend being 90°-180°.

[0011] In one embodiment, the thermomechanical cycle training includes: subjecting a nickel-titanium alloy hyaluronic acid tube in a straight state to high-temperature heat treatment, causing it to exhibit a first-direction bending state in a high-temperature phase state; placing the nickel-titanium alloy hyaluronic acid tube in an intermediate temperature state and applying an external force, causing it to form a second-direction bending state; and cyclically switching the nickel-titanium alloy hyaluronic acid tube between a high-temperature phase state, a low-temperature phase state, and an intermediate temperature state to stabilize its two-way shape memory response.

[0012] In one embodiment, the high-temperature heat treatment temperature is 500°C, the heat treatment time is 25-40 minutes, and the number of cycles is not less than 1000.

[0013] Preferably, the local heating element includes an optical fiber, the guide wire core is provided with an optical fiber channel, the optical fiber passes through the optical fiber channel, and the far end of the optical fiber is oriented towards the curved section.

[0014] In one embodiment, the inner wall of the curved section is provided with a photothermal conversion coating, and the distal end of the optical fiber corresponds to the photothermal conversion coating, so that the light energy output by the optical fiber is converted into heat energy acting on the curved section by the photothermal conversion coating.

[0015] In a preferred embodiment, the nickel-titanium alloy subwoofer further includes a transition section and a support section, the transition section being connected between the bending section and the support section, and the bending section, the transition section and the support section having different cutting structures to create a gradual change in stiffness from the distal end to the proximal end of the nickel-titanium alloy subwoofer.

[0016] In another preferred embodiment, the adjustable bendable microwire further includes a development spring disposed at the distal end of the guidewire and located within a nickel-titanium alloy hyaluronic acid tube, for displaying the position and bending state of the bend.

[0017] (III) Beneficial Effects This invention provides an adjustable-bend microguidewire. Compared with the prior art, it has the following advantages: By setting up a guidewire mandrel, a nickel-titanium alloy thiocyanate tube bending section at the distal end of the guidewire, and a local heating element corresponding to the distal bending section, and by training the bending section through thermomechanical cycles to form a two-way shape memory response, the local heating element can locally heat the bending section and trigger the bending section to switch between a straight state and a preset bending state. This allows the microguidewire to complete distal direction adjustment without relying on a mechanical traction wire that runs through the entire length. This reduces response lag, friction loss, and unintended proximal deformation caused by long-distance traction transmission, and improves the bending stability and control precision of the microguidewire in complex vascular pathways.

[0018] By making the curved segment present a straight state, a first-direction curved state, and a second-direction curved state under different temperature conditions, and further defining the temperature range of the first temperature state, the morphological changes of the curved segment can correspond to the preset temperature state. This allows the operator to select different distal morphologies by controlling the heat supply intensity, thereby improving the ability of the microguidewire to select the direction at vascular bifurcation, tortuous vessels, or lesion entry points.

[0019] By setting an optical fiber channel within the guidewire mandrel and positioning the distal end of the fiber towards the bending section, while simultaneously applying a photothermal conversion coating to the inner wall of the bending section, external light energy can be concentrated and converted into heat energy acting on the bending section, improving the concentration and response efficiency of local heating. By setting transition sections, support sections, and different cutting structures to create a gradual change in stiffness, and by setting a radiopaque spring to display the position and bending state of the bending section, the distal flexibility, proximal support, and intraoperative visualization requirements of the microguidewire can be balanced. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure of the adjustable bendable microguidewire provided by the present invention.

[0022] Figure 2 This is a partial cross-sectional view of the distal end of the adjustable bendable microguidewire provided by the present invention.

[0023] Figure 3 This is a cross-sectional view of the guide wire mandrel provided by the present invention.

[0024] Figure 4 This is a schematic diagram of the end face structure of the guide wire mandrel provided by the present invention.

[0025] Figure 5 This is a schematic diagram illustrating the relationship between martensite content and phase transformation temperature, as provided by the present invention.

[0026] Figure 6 This is a schematic diagram showing the morphological changes of the curved segment under different temperature conditions provided by the present invention.

[0027] The attached figures are labeled as follows: 10. Guide wire mandrel; 11. Fiber optic channel; 20. Nickel-titanium alloy hyaluronic acid tube; 21. Bending section; 22. Photothermal conversion coating; 23. Transition section; 24. Support section; 30. Optical fiber; 40. Developing spring. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1 like Figures 1-4 As shown, this embodiment provides an adjustable microwire, including a guidewire mandrel 10, a nickel-titanium alloy hyaluronic acid tube 20, a local heating element, and a developing spring 40. The nickel-titanium alloy hyaluronic acid tube 20 is disposed on the outside of the guidewire mandrel 10. The guidewire mandrel 10 extends along the axial direction of the microwire and penetrates from the distal end to the proximal end of the microwire to provide pushing support and torque transmission basis for the microwire. The nickel-titanium alloy hyaluronic acid tube 20 is used to form a flexible external support structure at the distal end of the microwire.

[0030] The nickel-titanium alloy hypotube 20 includes a curved section 21 at the distal end, a transition section 23 connected to the curved section 21, and a support section 24 connected to the transition section 23. The transition section 23 is located between the curved section 21 and the support section 24. The curved section 21, the transition section 23, and the support section 24 have different cutting structures, which makes the nickel-titanium alloy hypotube 20 form a gradual change in stiffness from the distal end to the proximal end. Specifically, the cutting density of the curved section 21 is greater than that of the transition section 23, and the cutting density of the transition section 23 is greater than that of the support section 24, so that the curved section 21 has better bending response capability, the transition section 23 is used to achieve a smooth transition, and the support section 24 is used to maintain the support and pushing properties of the microguidewire in the proximal direction.

[0031] In a specific structure, the bending section 21 can be configured as a spiral cutting section, an interlaced cutting section, or an annular cutting section arranged at intervals along the axial direction; the transition section 23 can be configured as a transition cutting section with gradually increasing slit spacing; and the support section 24 can be configured as a section with few cuts or no cuts, so that the bending section 21 can preferentially deform without weakening the overall support.

[0032] The guidewire mandrel 10 can be made of stainless steel, such as 304 stainless steel. The guidewire mandrel 10 is gradually ground from the proximal end to the distal end, so that the distal end has higher compliance than the proximal end, so that the microguidewire can take into account both proximal push and distal compliance when advancing in the blood vessel. The distal end of the guidewire mandrel 10 can also be provided with a flattened section. The flattened section can improve the compliance of the distal end during bending and reduce the rigid interference of the guidewire mandrel 10 when the bending section 21 is deformed by heat.

[0033] The local heating element is an optical fiber 30. The guide wire core 10 is provided with an optical fiber channel 11 extending along its length. The optical fiber 30 passes through the optical fiber channel 11 and extends from the proximal end of the microguide wire to the distal end of the microguide wire. The distal end of the optical fiber 30 is positioned towards the bending section 21 so as to transmit the light energy output by the external laser to the corresponding position of the bending section 21.

[0034] The inner wall of the bent section 21 is provided with a photothermal conversion coating 22. The photothermal conversion coating 22 is located on the light output path at the far end of the optical fiber 30. After the light energy output by the optical fiber 30 irradiates the photothermal conversion coating 22, the photothermal conversion coating 22 converts the light energy into heat energy and locally transfers the heat to the bent section 21, causing the bent section 21 to heat up to the corresponding temperature state.

[0035] The photothermal conversion coating 22 can be partially disposed circumferentially along the inner wall of the curved section 21, or it can be extended axially along the inner wall of the curved section 21. When it is necessary to improve the controllability of the bending direction, the photothermal conversion coating 22 is preferably disposed on one side of the inner wall of the curved section 21, so that the light energy output by the optical fiber 30 is preferentially applied to one side of the curved section 21, thereby causing the curved section 21 to form directional deformation when heated.

[0036] The imaging spring 40 is located at the distal end of the microguidewire and inside the nickel-titanium alloy hypotube 20. The imaging spring 40 can at least partially surround the distal outer side of the guidewire core 10 and correspond axially to the bending section 21. The imaging spring 40 is used to display the position of the distal end of the microguidewire and the bending state of the bending section 21 under X-ray, so that the operator can determine whether the microguidewire has reached the target blood vessel area and whether the bending direction is as expected.

[0037] like Figure 5 As shown, Figure 5This diagram illustrates the relationship between martensite content and phase transformation temperature, where the horizontal axis represents the phase transformation temperature and the vertical axis represents the martensite content. When the temperature of the bending section 21 rises to the initiation temperature As of the reverse martensitic transformation, the nickel-titanium alloy material in the bending section 21 begins to transform from the martensitic phase to the austenitic phase. When the temperature further rises to the end temperature Af of the reverse martensitic transformation, the nickel-titanium alloy material in the bending section 21 transforms into the austenitic phase. Conversely, when the temperature of the bending section 21 decreases to the initiation temperature Ms of the martensitic transformation, the nickel-titanium alloy material in the bending section 21 begins to transform from the austenitic phase to the martensitic phase. When the temperature further decreases to the end temperature Mf of the martensitic transformation, the nickel-titanium alloy material in the bending section 21 transforms into the martensitic phase.

[0038] In one specific embodiment, in order to adapt the direction adjustment process of the microguidewire to the human body's usage environment and facilitate temperature trigger control, the phase transition temperature of the bending section 21 can be set as follows: As is 45°C, Af is 50°C, Ms is 40°C, and Mf is 37°C, where Mf corresponds to the vicinity of the human body temperature, so that the bending section 21 can remain in a straight state under body temperature conditions when it is not actively heated or when heating is stopped.

[0039] This embodiment employs a thermomechanical cycle training method based on the phase transition region to induce a two-way shape memory effect in the bending segment 21 at the tip of the microguidewire. By repeatedly constraining and aging the shape under high temperature and low temperature phases, the bending segment 21 can present a specific preset bending state under different temperature conditions, thereby achieving reversible adjustment of the distal direction of the microguidewire as the temperature changes.

[0040] The bending segment 21 is a bending segment that has formed a two-way shape memory response through thermomechanical cycle training. The bending segment 21 can be in a straight state at a first temperature state, in a bending state in a first direction at a second temperature state, and in a bending state in a second direction at a third temperature state. The bending directions of the first bending state and the second bending state are different.

[0041] Specifically, the first temperature state can be 35℃-38℃, the second temperature state can be 39℃-42℃, and the third temperature state can be 45℃-52℃; preferably, the first temperature state is around 37℃, the second temperature state is around 40℃, and the third temperature state is around 50℃. The curved segment 21 is straight in the first temperature state, right-bent in the second temperature state, and left-bent in the third temperature state, and the bending angle of the right-bent and left-bent states can be 90°-180°.

[0042] The thermomechanical cycle training of the bending section 21 can be carried out in the following way: First, select the nickel-titanium alloy hyaluronic acid tube 20 corresponding to the bending section 21 and keep it in a straight state in the low-temperature phase state corresponding to the Mf temperature. Then, put the nickel-titanium alloy hyaluronic acid tube 20 into the first shaping fixture. The first shaping fixture has a first direction bending shaping groove. The bending angle of the first direction bending shaping groove can be 90° or 180°. After constraining the nickel-titanium alloy hyaluronic acid tube 20 in the first direction bending shaping groove, perform high-temperature heat treatment so that it forms a first direction bending memory shape in the high-temperature phase state corresponding to the Af temperature.

[0043] In one specific training method, the high-temperature heat treatment temperature is 500℃, the heat treatment time is 25-40min, and after the heat treatment is completed, it is cooled to give the nickel-titanium alloy hyaluronic acid tube 20 a memory basis of bending in the first direction in the high-temperature phase state; the first direction here can be the left bending direction, or it can be set to the right bending direction according to the actual product needs.

[0044] The nickel-titanium alloy hyaluronic acid tube 20, after high-temperature heat treatment, is placed in an intermediate temperature state corresponding to Ms temperature, such as a water bath at 39℃-42℃, and then placed into a second shaping fixture. The second shaping fixture has a second-direction bending shaping groove, the bending direction of which is opposite to that of the first-direction bending shaping groove. The second shaping fixture applies a constraint force to the nickel-titanium alloy hyaluronic acid tube 20, causing the nickel-titanium alloy hyaluronic acid tube 20 to form a second-direction bending state.

[0045] Subsequently, the nickel-titanium alloy hyaluronic acid tube 20 is placed in a water bath corresponding to temperature Af to restore it to the first direction bending state. Then, the nickel-titanium alloy hyaluronic acid tube 20 is placed in a water bath corresponding to temperature Mf to restore or maintain a straight state. The process of second direction constraint in the intermediate temperature state, first direction recovery in the high temperature phase state, and straight line recovery in the low temperature phase state is repeated to stabilize its two-way shape memory response.

[0046] In a preferred training method, the low temperature phase corresponds to 35℃-38℃, the intermediate temperature phase corresponds to 39℃-42℃, and the high temperature phase corresponds to 45℃-52℃, with the number of cyclic switching cycles not less than 1000. After the cyclic training is completed, the bending segment 21 can maintain a straight state in the first temperature state, exhibit a bending state in the second direction in the second temperature state, and exhibit a bending state in the first direction in the third temperature state.

[0047] In this embodiment, if the first direction is set as a left-bending direction and the second direction is set as a right-bending direction, the bending segment 21 after training will be in a straight state near 37°C, in a right-bending state near 40°C, and in a left-bending state near 50°C. When different bending angles are required, the bending segment 21 can obtain a target bending response of 90° or 180° by adjusting the bending shaping groove angle of the first shaping fixture and the second shaping fixture, the heat preservation time, the constraint aging conditions, or the number of cycles.

[0048] In actual use, the operator can adjust the output power and pulse width of the laser so that the optical fiber 30 can transmit light energy to the photothermal conversion coating 22 in the bending section 21, and the photothermal conversion coating 22 can convert the light energy into heat energy, so that the bending section 21 is heated to the corresponding temperature range, thereby triggering the bending section 21 to switch between a straight state, a first-direction bending state, and a second-direction bending state.

[0049] When the distal end of the microguidewire needs to remain straight for advancement, the laser output can be stopped or reduced, allowing the curved segment 21 to maintain or return to the first temperature state under the cooling effect of blood flow and heat conduction. When the distal end of the microguidewire needs to enter a bifurcation vessel or adjust its direction, the laser output can be increased, allowing the curved segment 21 to reach the second or third temperature state, thereby causing the curved segment 21 to bend in the corresponding direction and achieving distal direction adjustment.

[0050] Since the deformation of the bending segment 21 is completed by its own two-way shape memory response and local heating triggering of the local heating element, the microguidewire does not need to be equipped with a traction wire running through the entire length, nor does it need to drive the distal bending through the proximal mechanical traction, which can reduce the response delay, friction loss and unintended proximal deformation caused by long-distance mechanical transmission.

[0051] Example 2 The adjustable bendable microguidewire of this embodiment also includes a guidewire mandrel 10, a nickel-titanium alloy hysteresis tube 20, and a local heating element. The nickel-titanium alloy hysteresis tube 20 is disposed on the outside of the guidewire mandrel 10 and has a bending section 21, a transition section 23, and a support section 24. The bending section 21 is trained by thermomechanical cycle to form a two-way shape memory response, which can present a straight state, a first-direction bending state, and a second-direction bending state under different temperature conditions.

[0052] In this embodiment, the local heating element may include a micro resistance wire, a thin film heating element, or a conductive heating layer. The micro resistance wire, thin film heating element, or conductive heating layer is disposed on the inner side, outer side, or near the wall of the bending section 21, and extends to the proximal end of the micro guide wire through a conductive connector. After being energized, the local heating element can generate heat at the corresponding position of the bending section 21, so that the bending section 21 is heated to a preset temperature.

[0053] To avoid the local heating element from significantly affecting the overall pushing performance of the microguide wire, the local heating element is preferably arranged locally along the axial direction of the bending section 21, and its axial length is less than or equal to the axial length of the bending section 21. The local heating element can be set in one side of the bending section 21 so that one side of the bending section 21 is heated preferentially during heating, thereby improving the response efficiency and directional stability in the bending direction.

[0054] When a thin-film heating element or a conductive heating layer is used, it can be set on the inner wall surface of the bending section 21 and separated from the wire core 10 by an insulating layer. The insulating layer is used to reduce the leakage of current to the wire core 10 and at the same time reduce the influence of the wire core 10 on the local temperature rise of the bending section 21, so that the heat is mainly concentrated on the bending section 21.

[0055] In this embodiment, the thermomechanical cycle training process of the bending segment 21 is the same as that in Embodiment 1. First, the nickel-titanium alloy hysteresis tube 20 is subjected to high-temperature heat treatment to obtain the memory basis of the first direction bending state. Then, it is subjected to external force constraint under intermediate temperature state to form the second direction bending state. Finally, by repeatedly switching between high-temperature phase state, low-temperature phase state and intermediate temperature state, the bending segment 21 can stably obtain a two-way shape memory response.

[0056] When in use, when the local heating element is not energized or is energized at low power, the bending section 21 is in a first temperature state and is in a straight state; when the local heating element outputs power at the first power, the bending section 21 heats up to a second temperature state and is in a first direction bending state; when the local heating element outputs power at the second power, the bending section 21 heats up to a third temperature state and is in a second direction bending state, wherein the second power can be greater than the first power.

[0057] In this embodiment, by replacing the optical fiber 30 and the photothermal conversion coating 22 with a resistive local heating structure, it is still possible to achieve local heating of the bent section 21 and trigger the bent section 21 to switch between a straight state and a preset bent state.

[0058] Example 3 In this embodiment, the inner wall of the curved section 21 may be provided with multiple photothermal conversion coatings 22, and the multiple photothermal conversion coatings 22 are arranged at intervals along the circumference of the curved section 21; correspondingly, the local heating component may include multiple optical fibers 30, and the multiple optical fibers 30 are respectively arranged corresponding to the multiple photothermal conversion coatings 22, so that different optical fibers 30 can respectively transmit light energy to different circumferential areas of the curved section 21.

[0059] The inner wall of the curved section 21 can be provided with a first photothermal conversion coating and a second photothermal conversion coating. The first photothermal conversion coating is located in the left inner wall area of ​​the curved section 21, and the second photothermal conversion coating is located in the right inner wall area of ​​the curved section 21. The distal end of the first optical fiber is set towards the first photothermal conversion coating, and the distal end of the second optical fiber is set towards the second photothermal conversion coating. By controlling the light input of the first optical fiber and the second optical fiber respectively, different circumferential areas of the curved section 21 can be heated, thereby improving the controllability of left bend, right bend or spatial multi-directional adjustment.

[0060] In another structure, multiple photothermal conversion coatings 22 can be set in three or four locations along the circumference of the curved section 21, corresponding to the upper, lower, left and right heating areas; by selectively activating the corresponding optical fiber 30, the curved section 21 can be made to bend in different directions to adapt to the guidance requirements under complex paths such as intracranial bifurcation vessels, tortuous vessels or aneurysm entrances.

[0061] In this embodiment, the bending segment 21 is still a nickel-titanium alloy hyaluronic acid tube segment that has formed a two-way shape memory response through thermomechanical cycle training. The arrangement of multiple photothermal conversion coatings 22 and multiple optical fibers 30 is used to further improve the selectivity of the local heating position. In this embodiment, the bending segment 21 can be switched to a preset shape by different temperature states, and the bending direction control can be enhanced by selecting different circumferential heating areas.

[0062] In this embodiment, the imaging spring 40 is still located at the distal end of the guidewire and inside the nickel-titanium alloy hysteresis tube 20. The imaging spring 40 corresponds to the bending section 21 in the axial direction, so that the operator can observe the bending direction and bending angle of the bending section 21 after different optical fibers 30 are heated under the imaging device, and adjust the light input state according to the image feedback.

[0063] In the above embodiments, the outer surface of the nickel-titanium alloy hypotube 20 can also be provided with a hydrophilic coating to reduce the frictional resistance between the microguidewire and the blood vessel wall when it is advanced in the blood vessel; the hydrophilic coating can cover the outer surface of the curved section 21, the transition section 23 and the support section 24, or it can cover only a part of the distal end of the microguidewire as needed.

[0064] In this invention, the first direction and the second direction are only used to distinguish different bending directions and are not limited to a fixed left or right side. In actual products, the first direction can be set to any one of left bend, right bend, up bend or down bend according to the thermomechanical cycle training direction of the bending segment 21, the position of the photothermal conversion coating 22 and the arrangement of the local heating element, and the second direction can be set to another direction different from the first direction.

[0065] Through the above structure, the present invention can utilize the nickel-titanium alloy hyaluronic acid tube 20 trained by thermomechanical cycles to form a two-way shape memory response, and use a local heating element to locally heat the bending section 21, so that the bending section 21 presents a straight state and a preset bending state under different temperature conditions, thereby achieving controllable adjustment of the distal direction of the microguide wire without relying on the mechanical traction wire.

[0066] In summary, compared with the prior art, the adjustable microguidewire proposed in this application has the following beneficial effects: By setting up a guidewire mandrel 10, a bent section 21 of a nickel-titanium alloy hypotube 20 located at the distal end of the guidewire, and a local heating element corresponding to the bent section 21 at the distal end, and by enabling the bent section 21 to form a two-way shape memory response through thermomechanical cycle training, the local heating element can locally heat the bent section 21 and trigger the bent section 21 to switch between a straight state and a preset bent state. This allows the microguidewire to complete distal direction adjustment without relying on a mechanical traction wire that runs through the entire length, reducing response lag, friction loss, and unintended proximal deformation caused by long-distance traction transmission, and improving the bending stability and control accuracy of the microguidewire in complex vascular pathways.

[0067] By making the curved segment 21 present a straight state, a first-direction curved state, and a second-direction curved state under different temperature conditions, and further defining the temperature range of the first temperature state, the morphological changes of the curved segment 21 can correspond to the preset temperature state. This allows the operator to select different distal morphologies by controlling the heat supply intensity, thereby improving the ability of the microguidewire to select the direction at vascular bifurcation, tortuous vessels, or lesion entry points.

[0068] By setting an optical fiber channel 11 inside the guidewire core 10 and positioning the distal end of the optical fiber 30 toward the bending section 21, and simultaneously setting a photothermal conversion coating 22 on the inner wall of the bending section 21, external light energy can be concentrated and converted into heat energy acting on the bending section 21, thereby improving the concentration and response efficiency of local heating. By setting a transition section 23, a support section 24, and different cutting structures to form a gradual change in stiffness, and setting a imaging spring 40 to display the position and bending state of the bending section 21, the distal flexibility, proximal support, and intraoperative visualization judgment requirements of the microguidewire can be taken into account.

[0069] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0070] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An adjustable bending micro-wire, characterized in that, The guide wire mandrel (10), the nickel-titanium alloy hypotube (20), and the local heating element are included. The nickel-titanium alloy hypotube (20) is arranged outside the guide wire mandrel (10), and the nickel-titanium alloy hypotube (20) has a curved section (21) at the distal end. The curved section (21) is a curved section formed by a thermal mechanical cycle training to have a two-way shape memory response, and the curved section (21) can correspondingly present a straight state and a preset curved state under different temperature states. The distal end of the local heating element corresponds to the curved section (21) and is arranged for locally heating the curved section (21) to trigger the curved section (21) to switch between the straight state and the preset curved state.

2. The adjustable bending microguide wire of claim 1, wherein, The curved section (21) can present a straight state under a first temperature state, a first direction curved state under a second temperature state, and a second direction curved state under a third temperature state, and the curved directions of the first direction curved state and the second direction curved state are different.

3. The adjustable bending microguide wire of claim 2, wherein, The first temperature state is 35-38℃, the second temperature state is 39-42℃, and the third temperature state is 45-52℃.

4. The adjustable bending microguide wire of claim 2, wherein, The curved section (21) presents a straight state under a first temperature state, a right curved state under a second temperature state, and a left curved state under a third temperature state, and the curved angles of the right curved state and / or the left curved state are 90-180°.

5. The adjustable bending microguide wire of claim 1, wherein, The thermal mechanical cycle training includes: high-temperature heat treatment is performed on the nickel-titanium alloy hypotube (20) in a straight state to make it present a first direction curved state under a high-temperature phase state; the nickel-titanium alloy hypotube (20) is placed under an intermediate temperature state and an external force is applied to make it form a second direction curved state, and the nickel-titanium alloy hypotube (20) is switched between the high-temperature phase state, the low-temperature phase state, and the intermediate temperature state to stabilize its two-way shape memory response.

6. The adjustable bending microguide wire of claim 5, wherein, The temperature of the high-temperature heat treatment is 500℃, the heat treatment time is 25-40 min, and the number of the cycle switching is not less than 1000 times.

7. The adjustable bend microguide wire of claim 1, wherein, The local heating element includes an optical fiber (30), the guide wire mandrel (10) is provided with an optical fiber channel (11), the optical fiber (30) is arranged in the optical fiber channel (11), and the distal end of the optical fiber (30) is arranged towards the curved section (21).

8. The adjustable bend microguide wire of claim 7, wherein, An optical-thermal conversion coating (22) is arranged on the inner wall of the curved section (21), and the distal end of the optical fiber (31) corresponds to the optical-thermal conversion coating (22) to make the light energy output by the optical fiber (30) converted into thermal energy acting on the curved section (21) through the optical-thermal conversion coating (22).

9. The adjustable bend microguide wire of claim 1, wherein, The nickel-titanium alloy hypotube (20) further includes a transition section (23) and a support section (24), the transition section (23) is connected between the curved section (21) and the support section (24), and the curved section (21), the transition section (23), and the support section (24) have different cutting structures to make the nickel-titanium alloy hypotube (20) have a gradually changing rigidity from the distal end to the proximal end.

10. The adjustable bending microguide wire of claim 1, wherein, A developing spring (40) is further included, the developing spring (40) is arranged at the distal end of the guide wire and located in the nickel-titanium alloy hypotube (20) to show the position and the curved state of the curved section (21).

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