Bending actuator, manufacturing method of bending actuator and bending execution assembly

Abstract

The invention discloses a bending actuator, a manufacturing method of the bending actuator and a bending execution assembly, and the bending actuator comprises a micro-catheter which is of a hollow structure; the shape memory component is located in the microcatheter far end, the far end of the shape memory component is of a bent structure, and the curvature of the bent structure at different temperatures is different. According to the design, the position of the far end of the micro catheter can be accurately controlled.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to a bending actuator, a method for preparing a bending actuator, and a bending actuator assembly. Background Art

[0002] Currently, selective internal radiation therapy (SIRT) has shown significant effects in the treatment of liver cancer, but due to the complexity and variability of arterial anatomical structure, existing single-lumen microcatheters cannot accurately target the tumor site, resulting in damage to healthy liver tissue.

[0003] In clinical practice, controlling the position of the microcatheter is crucial to ensure the success of the operation. At present, manual operation by doctors and computer-assisted navigation systems are common control methods in the prior art. Among them, manual operation is that the doctor controls the position of the microcatheter by adjusting the propulsion and rotation of the microcatheter. This method relies on the doctor's experience and skills and may not be accurate enough for some complex anatomical structures. The computer-assisted navigation system relies on high-quality imaging data, has a high dependence on equipment, and may cause patients to receive more radiation exposure. Therefore, there is an urgent need for a microcatheter that is both safer and more accurate. Summary of the invention

[0004] The present application provides a bending actuator, a method for preparing the bending actuator, and a bending actuator assembly, which can accurately control the position of the distal end of a microcatheter.

[0005] In a first aspect, the present application provides a bending actuator, which includes: a microcatheter having a hollow structure; a shape memory component located inside the distal end of the microcatheter, wherein the distal end of the shape memory component has a curved structure, and the curvature of the curved structure is different at different temperatures.

[0006] The material of the shape memory component is a shape memory alloy, the first curvature of the curved structure at a first temperature is greater than the second curvature at a second temperature, and the first temperature is greater than the second temperature.

[0007] The shape memory alloy is in the form of a wire or a ribbon.

[0008] Wherein, the bending actuator comprises: a wire, which is passed through the inside of the micro-catheter and is electrically connected to the shape memory alloy and is used to be electrically connected to an external power source.

[0009] Wherein, the material of the micro-catheter includes rigid or semi-rigid material.

[0010] Wherein, the proximal end of the shape memory component is a straight structure.

[0011] Wherein, at the first temperature, the first curvature of the curved structure is equal everywhere, and at the second temperature, the second curvature of the curved structure is equal everywhere; or, at the first temperature, the first curvature of the curved structure gradually increases in the direction from the proximal end to the distal end of the microcatheter, and at the second temperature, the second curvature of the curved structure gradually increases in the direction from the proximal end to the distal end of the microcatheter.

[0012] A second aspect of the present application provides a method for preparing a bending actuator, which is applied to the bending actuator described in any one of the above embodiments, and the method includes: shaping at least the distal end of the shape memory component to obtain the bending structure with a third curvature; placing the bending structure inside the distal end of the microcatheter; controlling the bending structure to be at the second temperature so that the curvature of the bending structure changes to the second curvature; controlling the bending structure to be at the first temperature so that the curvature of the bending structure changes to the first curvature.

[0013] Wherein, the third curvature is greater than or equal to 50m -1 , and less than or equal to 333m -1 .

[0014] A third aspect of the present application further provides a bending actuator assembly, which includes the bending actuator described in any one of the above embodiments.

[0015] Different from the prior art, the beneficial effects of the present application are as follows: the distal end of the shape memory component of the present application is a curved structure, the curvature of the curved structure is different at different temperatures, the curved structure is located inside the microcatheter, and by changing the temperature, the shape memory recovery ability of the curved structure of the shape memory component can be utilized to restore its shape to control the position change of the distal end of the microcatheter, thereby achieving the purpose of accurately controlling the distal end of the microcatheter. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0017] Figure 1 It is a structural schematic diagram of an embodiment of a process in which a shape memory member in a bending actuator of the present application changes from a second curvature to a first curvature;

[0018] Figure 2It is a structural schematic diagram of an embodiment of a process in which a shape memory member in a bending actuator of the present application changes from a third curvature to a second curvature;

[0019] Figure 3 is a schematic flow chart of a method for preparing a bending actuator of the present application;

[0020] Figure 4 It is a structural schematic diagram of an implementation mode of the bending actuator of the present application. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0022] In the present invention, when describing the puncture assembly, "distal" and "proximal" are used as directional words, which are commonly used terms in the field of interventional medical devices, where "distal" refers to the end away from the operator during the operation, and "proximal" refers to the end close to the operator during the operation.

[0023] See also Figure 1 The present application provides a bending actuator 10, which includes a microcatheter 100 and a shape memory component 200. The microcatheter 100 is a hollow structure; the shape memory component 200 is located inside the distal end A of the microcatheter 100, and the distal end A of the shape memory component 200 is a curved structure, and the curvature of the curved structure is different at different temperatures.

[0024] Specifically, the shape memory component 200 has a shape memory capability according to temperature changes. Specifically, when the temperature rises or falls, the curvature of the curved structure of the shape memory component 200 will change. Generally speaking, the curved structure of the shape memory component 200 has two shapes at different temperatures, namely, the shape of the low temperature phase and the shape of the high temperature phase. The curvature of the shape of the low temperature phase and the shape of the high temperature phase are different, and due to its shape memory capability, the change of curvature is determined. By controlling the change of temperature, the curved structure of the shape memory component 200 can be restored to a preset position, thereby achieving the purpose of accurately controlling its position. In the present application, the curved structure of the shape memory component 200 is placed in the hollow structure inside the distal end A of the microcatheter 100, and the position of the distal end A of the microcatheter 100 is accurately controlled by the shape memory of the curved structure of the shape memory component 200 at different temperatures. Compared with the prior art, which uses manual control of the microcatheter or a computer-assisted navigation system to assist in controlling the microcatheter, the present application can make the control of the position of the distal end of the microcatheter 100 more accurate on the one hand, and on the other hand, there is no need for a computer-assisted navigation system to assist, so there is no radiation to the human body and other problems, and the solution is safer.

[0025] In one embodiment, in combination Figure 1 and Figure 2 The material of the shape memory component 200 is a shape memory alloy, a first curvature of the curved structure at a first temperature is greater than a second curvature at a second temperature, and the first temperature is greater than the second temperature.

[0026] Specifically, the first temperature is greater than the second temperature, that is, the first temperature is a high temperature, and the second temperature is a low temperature. The shape memory alloy has a martensite phase shape at a low temperature and an austenite phase shape at a high temperature, wherein the shape of the martensite phase is the shape of the low temperature phase, and the shape of the austenite phase is the shape of the high temperature phase. Specifically, refer to Figure 2 The curved structure of the shape memory component 200 can be processed by shaping so that the curved structure has a third curvature, and then a microcatheter 100 is selected, and the curvature of the microcatheter 100 is smaller than the third curvature of the curved structure. Preferably, a microcatheter 100 with a rectangular cross-section can be selected, and the microcatheter 100 is placed on the curved structure. Since the microcatheter 100 is different from the curved structure, the microcatheter 100 will apply a preload force to the curved structure, and the curvature of the curved structure will decrease. At low temperature, the curved structure will transform into the shape of the martensitic phase by using the stress-induced martensitic phase transformation, and the curvature will become the second curvature at the second temperature. Figure 1By heating the curved structure at the second temperature to the first temperature, the temperature induces the martensite phase to transform into the austenite phase, the shape of the curved structure is restored, the curvature increases, and the curvature becomes the first curvature at the first temperature. Since the microcatheter 100 is sleeved on the outside of the curved structure of the shape memory component 200, the curved structure of the shape memory component 200 cannot be restored to the third curvature at the initial shaping, but it can also be determined by experiments or simulations. It can be understood that the first curvature is smaller than the third curvature, but greater than the second curvature.

[0027] It should be noted that the first curvature, the second curvature and the third curvature can all be calculated based on the central axis of the curved structure of the shape memory component 200. Of course, the curvature can also be calculated based on the contour line of the inner side or the outer side of the curved structure.

[0028] In one embodiment, the shape memory alloy is in a wire or ribbon shape, which can better match the shape of the micro-catheter 100 and is more convenient to shape.

[0029] Of course, in some other embodiments, the shape memory alloy is in a spiral shape or the like.

[0030] In one embodiment, the material of the microcatheter 100 includes a rigid or semi-rigid material. It is understood that since the shape memory alloy is a material with a certain rigidity, it can be used to induce the bending structure of the shape memory member 200 to transform into a martensite phase at low temperature through stress. Therefore, the material of the microcatheter 100 can be a rigid material, a semi-rigid material, or a material between rigidity and semi-rigidity. For example, the microcatheter 100 can be made of polydimethylsiloxane. By adjusting the thickness and size of the polydimethylsiloxane, the rigidity of the microcatheter 100 can be adjusted, thereby adjusting the first curvature and the second curvature of the bending actuator 10 at intervals.

[0031] Of course, in some embodiments, instead of inducing the bending structure to transform into the martensitic phase through a microcatheter, other auxiliary components are used to apply a preload to induce the bending structure to transform into the martensitic phase through stress, and finally a microcatheter made of flexible material is put onto the bending structure.

[0032] In one embodiment, see Figure 1 , the proximal end B of the shape memory member 200 is in a straight structure.

[0033] Specifically, the curved structure of the shape memory component 200 is used to accurately control the position of the distal end A of the microcatheter 100, while the proximal end B is no longer a curved structure. The straight structure can increase the overall length of the shape memory component 200, thereby extending the control distance of the shape memory component 200 and further increasing the penetration depth of the microcatheter 100. Of course, the proportion of the curved structure and the straight structure in the length of the shape memory component 200 is not limited in this application and can be adjusted accordingly according to the situation.

[0034] In one embodiment, the bending actuator 10 includes a wire (not shown), which is passed through the microcatheter 100 and is electrically connected to the shape memory member 200 for being electrically connected to an external power source.

[0035] Specifically, the wire and the shape memory component 200 are both sleeved inside the microcatheter 100, and therefore, will not have any effect on the human body. The external power supply supplies power to the shape memory component 200 through the wire, and the bending structure of the shape memory component 200 is induced to change from the shape of the martensite phase to the shape of the austenite phase through current heating, and the curvature is changed from the second curvature to the first curvature, thereby accurately controlling the position of the distal end A of the microcatheter 100.

[0036] In one embodiment, see Figure 1 At the first temperature, the first curvature of the bending structure is equal everywhere, and at the second temperature, the second curvature of the bending structure is equal everywhere. In other words, the curvature of the bending structure is equal everywhere, which can make the preparation cost of the bending actuator 10 lower.

[0037] In one embodiment, at a first temperature, the first curvature of the curved structure gradually increases in the direction from the proximal end B to the distal end A of the microcatheter 100, and at a second temperature, the second curvature of the curved structure gradually increases in the direction from the proximal end B to the distal end A of the microcatheter 100. In other words, the curved structure may be composed of multiple curved substructures with different curvatures, and the closer to the distal end A, the greater the curvature, and such a design is more conducive to accurately controlling the position of the distal end A of the microcatheter 100.

[0038] Combination Figures 1 to 3 The present application also provides a method for preparing a bending actuator 10, which is applied to the bending actuator 10 in any of the above embodiments, and the method comprises:

[0039] S100: shaping at least the distal end A of the shape memory member 200 to obtain a curved structure having a third curvature.

[0040] Specifically, this step is to shape the portion of the shape memory component 200 on the side of the distal end A so that the portion is shaped into a curved structure with a third curvature, and when it subsequently transforms from the martensite phase to the austenite phase, the curvature is restored to the third curvature.

[0041] In one application scenario, a clamp is used to fix the distal end A of the shape memory alloy into a structure with a third curvature, which is then placed in a high-temperature furnace for heating and then quenched at room temperature to obtain a curved structure.

[0042] S200 : placing a curved structure inside the distal end A of the microcatheter 100 .

[0043] Specifically, after the curved structure is shaped, the microcatheter 100 is sleeved on the curved structure, and a preload force is applied to the curved structure, so that stress is generated inside the curved structure. Preferably, the axial cross-section of the microcatheter 100 is rectangular. It should be noted that the microcatheter used in the preparation and the microcatheter at the product end can be the same microcatheter or different microcatheters, and this application does not limit this.

[0044] S300: controlling the curved structure to be at a second temperature so that the curvature of the curved structure changes to a second curvature.

[0045] Specifically, the curved structure is placed at the second temperature by utilizing stress-induced martensitic phase transformation, thereby inducing the curvature of the curved structure to change from the third curvature to the second curvature, and the second curvature is smaller than the third curvature.

[0046] S400: controlling the curved structure to be at a first temperature so that the curvature of the curved structure changes to a first curvature.

[0047] Specifically, when the curved structure is changed from an environment of the second temperature to an environment of the first temperature, the curved structure changes from a martensite phase to an austenite phase, and the curved structure recovers its shape, so that the curvature changes from the second curvature to the first curvature.

[0048] In one application scenario, the curved structure can be connected to a power source and heated by passing an electric current so that the curvature of the curved structure becomes a first curvature, where the first curvature is greater than the second curvature but less than the third curvature.

[0049] It can be seen from the above process that the bending actuator 10 prepared in the present application can ultimately achieve a change in the curvature of its bending structure by changing the temperature, thereby achieving the purpose of accurately controlling the position of the distal end A of the microcatheter 100.

[0050] In one embodiment, the third curvature is greater than or equal to 50 m -1 , and less than or equal to 333m -1 Specifically, the third curvature can be 50m -1 、150m-1 or 330m -1 By setting the curved structure into the above curvature, a better position control effect can be obtained.

[0051] The present application further provides a bending actuator assembly 20 , which includes the bending actuator 10 in any one of the above-mentioned embodiments.

[0052] It should be noted that the detailed structure of the bending actuator 10 in the bending actuator assembly 20 can refer to the above-mentioned embodiment of the bending actuator 10, which will not be repeated here; since the above-mentioned bending actuator 10 is used in the bending actuator 20 of the present application, the embodiment of the bending actuator 20 of the present application includes all technical solutions of all the embodiments of the above-mentioned bending actuator 10, and the technical effects achieved are also exactly the same, which will not be repeated here.

[0053] The above description is only an embodiment of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A bending actuator, characterized in that: The bending actuator comprises: Microcatheters are hollow structures; The shape memory component is located inside the distal end of the micro-catheter. The distal end of the shape memory component is a curved structure, and the curvature of the curved structure is different at different temperatures.

2. The bending actuator according to claim 1, characterized in that: The shape memory component is made of shape memory alloy, a first curvature of the curved structure at a first temperature is greater than a second curvature at a second temperature, and the first temperature is greater than the second temperature.

3. The bending actuator according to claim 2, characterized in that: Shape memory alloys are in the form of wires or ribbons.

4. The bending actuator according to claim 2, characterized in that: The bending actuator comprises: A conducting wire is passed through the micro-catheter and is electrically connected to the shape memory alloy and is used for being electrically connected to an external power source.

5. The bending actuator according to claim 1, characterized in that: The material of the micro-catheter includes a rigid or semi-rigid material.

6. The bending actuator according to claim 1, characterized in that: The proximal end of the shape memory component is in a straight structure.

7. The bending actuator according to claim 2, characterized in that: At the first temperature, the first curvature of the curved structure is equal everywhere, and at the second temperature, the second curvature of the curved structure is equal everywhere; or, At the first temperature, the first curvature of the curved structure gradually increases in the direction from the proximal end to the distal end of the microcatheter, and at the second temperature, the second curvature of the curved structure gradually increases in the direction from the proximal end to the distal end of the microcatheter.

8. A method for preparing a bending actuator, characterized in that: The method is applied to the bending actuator described in any one of claims 1 to 7, and the method comprises: shaping at least the distal end of the shape memory member to obtain the curved structure having a third curvature; placing the curved structure inside the distal end of the microcatheter; controlling the curved structure to be at the second temperature so that the curvature of the curved structure changes to the second curvature; The curved structure is controlled to be at the first temperature so that the curvature of the curved structure changes to the first curvature.

9. The method according to claim 8, characterized in that The third curvature is greater than or equal to 50m -1 , and less than or equal to 333m -1 .

10. A bending actuator, characterized in that: The bending actuator assembly comprises the bending actuator according to any one of claims 1-7.

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